Long Range Acoustic Device

The Long-Range Acoustic Device (LRAD) is an acoustic hailing device, sound cannon and sonic weapon[1] developed by Genasys. Law enforcement organizations and the manufacturer claim that LRAD systems are primarily designed for long-range communications;[2] however, the device has an extremely high decibel capacity and is controversially used as a less-lethal weapon for crowd control. The Academy of Doctors of Audiology states that 'Individuals exposed to weaponized LRAD use at the 2009 G20 Summit experienced mild traumatic brain injuries, permanent hearing loss, tinnitus (ringing in the ears), eardrum perforation (holes), ear pain, dizziness, and disorientation.'[3]

A LRAD on top of a New York City police Hummer.

According to the manufacturer's specifications, the systems weigh from 15 to 320 pounds (6.8 to 145.1 kg) and can emit sound in a 30–60° beam at 2.5 kHz.[4] The manufacturer also produces systems for public address and mass notification use that broadcast 360°.[5]

LRAD systems are used by law enforcement, government and defense agencies, as well as maritime and commercial security companies to broadcast audible notifications and warnings over distance. LRAD systems are also used to deter wildlife from airport runways, wind and solar farms, nuclear power facilities, gas and oil platforms, mining and agricultural operations, and industrial plants.


LRAD operator wearing hearing protection

The parameter "ka", which is the wave number multiplied by the speaker radius, is often used to characterize sound source directivity. For this source, ka=19 at 2.5 kHz, and according to the LRAD data sheet, the beam angle of about 30 degrees total is what is predicted for a regular loudspeaker.[6]

Small spherical "point-source" acoustic devices follow the known inverse square law, which predicts the loss of 6 decibels (dB) per doubling of distance from the source, solely due to geometric spreading. Large speakers (or large arrays), such as these, have an interference pattern in the nearfield which produces peaks 6 dB higher than the output pressure and nulls where the pressure is essentially zero.[7] The larger the speaker, and the higher the frequency, the longer the effective nearfield. The nearfield for this device is approximately 8 metres (26 ft).[7]

LRAD on a U.S. Navy ship


In addition to its "voice" feature, which acts as a loudspeaker, the LRAD has an "alert" feature, which emits loud chirping sounds that have been reported to cause pain and hearing damage.[8] The LRAD is often considered to be a sonic weapon. The NYPD's LRAD use is being challenged in federal court.[8][1][9] Due to potential risks and a lack of studies on the health impact of sonic weapons, the ACLU recommends that their use on protesters be suspended.[9]

Deployments and usesEdit

United StatesEdit

An NYPD officer stands ready with the LRAD 500X at an Occupy Wall Street protest on November 17, 2011 near the city hall

An LRAD was present during protests of the 2004 Republican National Convention in New York City[10] but not used.[citation needed]

LRADs were used by the Pittsburgh PD during protests at the G20 Summit in September 2009. This was the first time it was used during a protest in the U.S.[11][12]

LRAD was reportedly used[13] by the Oakland Police Department during the clearance of the Occupy Oakland encampment on the morning of 25 October 2011.

LRAD was present, but not used, when the New York City Police department cleared Occupy Wall Street protestors from Zuccotti Park on the morning of 15 November 2011.[14]

LRAD was deployed during a NATO march in Chicago on May 20, 2012, at Michigan Ave. & Cermack.[15]

The Salisbury, MD Police Department acquired an LRAD in October 2013 with proceeds from their speed cameras.[16]

St. Louis County police used LRAD during protests surrounding the police shooting of Michael Brown in Ferguson, Missouri.[17] Reporter Mike Tobin commented while broadcasting from Ferguson, MO on 18 August, "It doesn't have the effect of crippling people. It's just loud, it's annoying, it lets you know something big and official is coming and that's what's happening now. They can also use it as a loudspeaker to tell people to get out of the way."[18]

On December 5, 2014, the NYPD utilized an LRAD, notifying approximately 100 protestors to disperse, during the protest of the police killing of Eric Garner in Midtown Manhattan.[19]

Myrtle Beach, South Carolina police obtained two LRAD systems through a federal grant in March 2015. Myrtle Beach police captain Marty Brown told the Myrtle Beach city council that "his department is getting the LRADs to enhance their communication capabilities be it with large crowds or for emergency announcements such as evacuation orders."[20]

The NYPD used a Long Range Acoustic Device during the Baltimore solidarity rally in Union Square on April 29, 2015. An NYPD pickup truck equipped with an LRAD parked near protesters and broadcast a looped warning message about staying off the streets and not blocking the sidewalks.[21]

The New Jersey State Police used an armored-vehicle-mounted LRAD to communicate with crowds denied entry to a June 7, 2015 concert after they began throwing bottles and tried to rush the gates outside MetLife Stadium.[22]

The Greensboro, NC Police Department (GPD) purchased an LRAD 300X and demonstrated it for reporters in November 2015. Captain Jonathan Franks with GPD says it can be used for alerts for everything from riots to missing children to weather disasters. "I am sure, positive, 100% that in certain instances it will be able to not only save one life but numerous lives," said Franks.[23]

Police in San Diego, CA used an LRAD on May 27, 2016 to order anti-Trump protesters to disperse.[24]

Police from several agencies, including North Dakota state troopers, the National Guard, and other law enforcement agencies from surrounding counties and states deployed two LRADs to clear a protest camp and blockades along Highway 1806. "Long Range Acoustic Devices, which emit an ear-splitting whine, were used intermittently throughout the day" one reporter wrote.[25] An LRAD was present again on 11/20/2016 at the bridge just north of the protesters camp on highway 1806.[citation needed]

The Columbus, OH Police Department (CPD) demonstrated a Long Range Acoustic Device to the local media on November 21, 2016. CPD expects to use the device for crowd control, barricaded suspect operations, and to communicate to residents during emergencies and natural disasters.[26]

The Washington D.C. Metropolitan Police Department used a LRAD at the January 21, 2017 Women's March.[27]

On February 17, 2017, the Princess Anne Police Department deployed its LRAD system at the request of the Maryland State Police to disperse an unruly concert crowd on the campus of the University of Maryland Eastern Shore. Chief Tim Bozman of the Princess Anne Police Department said, "Its a very good piece of equipment for incidents like this."[28]

The Mendocino County (California) Board of Supervisors approved the purchase of a Long Range Acoustic Device for the Mendocino County Sheriff's Office on April 18, 2017. "Sheriff Tom Allman said the device will aid in searches for missing persons, most often hunters and mushroom pickers, which cost the county tens of thousands of dollars. Allman recalled the 2011 search for Aaron Bassler, who had been accused of murdering two men in Fort Bragg and led law enforcement officers on an intense manhunt in the Noyo Basin, saying the LRAD might have made that search a little easier. He said it could also be used to warn residents in case of a tsunami. Last year, MCSO was able to test an LRAD out of a low-flying plane along the coast, and it proved sufficient. He also said the LRAD could prove a valuable asset in a barricaded-person situation (a person hiding out from officers in a building) to communicate from the outside of the building, which has happened before".[29]

The Phoenix, AZ city council approved the purchase of two LRAD 500X systems in November 2018. The speakers will “provide an ability for us to give clear and concise messages to groups of people whenever we find it necessary to communicate with them,” according to Sgt. Mercedes Fortune.[30]

Rochester NY police used verbal warnings and an LRAD to help disperse disorderly crowds during the August 2019 Puerto Rican Festival.[31]

Police utilized a Long Range Acoustic device to declare an unlawful assembly in downtown Phoenix, AZ on May 28, 2020 during the George Floyd protests. Multiple announcements were made in English and Spanish.[32]

During the same period, the LRAD was used at a protest in front of the Arkansas State Capitol.[33]

The Portland Police Bureau used a vehicle-mounted LRAD during the George Floyd protests on June 4, 2020 and on other occasions during the protests.[34][35][36]

The Seattle Police Department purchased an LRAD in response to claims that it did not adequately communicate orders to demonstrators during the summer 2020 protests.[37] SPD's use of its LRAD was alleged to have caused ear damage to a peaceful demonstrator, although an internal SPD review deemed the allegations to be unsustained.[38]

A BearCat mounted LRAD was used to emit voice messages and high-pitched sirens in Kenosha, WI on August 24, 2020 in front of the Kenosha County Courthouse to disperse crowds assembled in Civic Center Park as part of the Jacob Blake protests.[39][40][41]

Rochester, NY police used a Long Range Acoustic Device to make announcements to protesters that they were unlawfully in the roadway and obstructing traffic on September 12, 2020. The device was also used at the September 16, 2020 protest in front of the Rochester city hall.[42][43]

In September 2020 it was revealed that federal officials had explored the use of the device and the Active Denial System ("heat ray") to disperse civilians protesting outside the White House in June of that year, but had been advised that the National Guard was not currently in possession of either device.[44]

Protesters at the June 1, 2020 Washington, D.C. George Floyd protests said police gave little or no warning before employing aggressive tactics against them. A 2015 settlement requires federal police to give large crowds several loud dispersal orders before deploying chemical irritants and other dispersion tools. Using an LRAD to issue loud protest dispersal orders would have complied with the 2015 settlement requirement.[45][46]

The Cuyahoga County Sheriff’s Department purchased Long Range Acoustic Devices to improve the department's ability to issue dispersal orders clearly over long distances. The purchases resulted from the department's after-action report of the May 30, 2020 riot in downtown Cleveland.[47]

After receiving feedback last summer from protesters who said commands from on-scene officers were not clear or loud enough, the Seattle, WA mayor's office recommended purchasing an LRAD.[48]

On March 6, 2021, the Boulder Police Department used a toned warble noise from an LRAD in an effort to disperse a crowd of up to 800 students from the University of Colorado Boulder. The University Hill Incident occurred when code enforcement and members of Boulder Police’s Neighborhood Impact Team were unable to disperse partygoers who were congregating against Boulders public health order. LRAD was used after students and other partygoers began throwing rocks at SWAT vehicles and officers. [49]

On April 12, 2021, the Brooklyn Center, MN Police Department deployed a vehicle mounted LRAD outside of its headquarters to announce curfew violations and dispersal orders to a large crowd protesting the death of Daunte Wright.[50][51]

On July 3, 2021, Massachusetts State Police utilized an LRAD to secure a group of 11 suspects involved in the Sovereign Citizen movement. The group identified themselves as part of the "Rise of the Moors" movement, or "Moorish Americans". The self styled militia group was travelling between Rhode Island and Maine when an MSP trooper came across their convoy refueling. The group had multiple firearms in their possession, and admitted to not having proper carrying requirements. Several fled into the surrounding forest at which point the LRAD was deployed. The group was taken into custody without further incident. [52]

Czech RepublicEdit

On June 26, 2015, Czech Special Forces Police may have deployed an LRAD 500X during anti-immigration and anti-Islam protests in Brno, the second largest city in the Czech Republic.[53][54]

Police in Prague used a vehicle-mounted LRAD on 17 November 2020 to repeatedly alert protesters on Wenceslas Square to follow COVID restrictions and wear masks.”[55]


Bad Homburg's fire brigade and city police used an LRAD 100X system more than 60 times in the first half of 2020 for delivering COVID-19 information.[56]


Hellenic Police acquired two LRAD systems to be used at the Evros border. These were tested after the March 2020 migrant crisis at the border, triggered by the Turkish government. They are to be used as a deterrent against illegal border entry, as a notification system, as well as to handle aggressive actions against the Hellenic Armed Forces.[57][58]


Japan's Coast Guard used Long Range Acoustic Devices and other methods to expel a North Korean fishing flotilla from its waters in September 2017.[59]

In February 2009, the Japanese whaling fleet operating in Antarctic waters near Australia installed LRADs on their vessels. The device was used against activists of the Sea Shepherd Conservation Society.[60] The Japanese fleet later escalated the use of LRAD, deploying it against a Sea Shepherd helicopter carrying a camera crew.[61][62] Sea Shepherd noted that they had an LRAD of their own, but as of early 2010, had not put it into use[63] other than to play a recording of "Ride of the Valkyries" in the manner of attacking U.S. Army helicopters depicted in the 1979 film Apocalypse Now.[64]


LRAD was present, but not used because of current legal regulations during protests in Poland, including Million Marijuana March 2011 and Marsz Niepodległości (National Independence Day March) 2011 and 2012. Lacking a way to utilize the LRADs purchased to their full potential sparked an investigation suspecting corruption behind their acquisition. National Police Headquarters spokesman Mariusz Sokolowski defended the purchase of LRAD. He also stressed that the police decided to make this investment because, "We needed good sound reinforcement equipment. With numerous demonstrations and gatherings, police need a public address system that allows you to reach thousands of people."[65]

Municipal police in Gdańsk, Poznań, Kołobrzeg and other cities in Poland are using LRAD systems to deliver COVID-19 notifications.[66][67]


Local police in Leganés, Spain are using a vehicle-mounted LRAD to deliver alerts and notifications to residents during the country-wide COVID-19 lockdown. According to Citizen Security, Communication and local government spokesman, Oscar Oliveira, “Because the acoustic device can be heard inside of houses, we can inform older residents with mobility issues that all municipal resources are available through the Citizen Attention Service by calling 010.”[68]

United KingdomEdit

It was confirmed by the Ministry of Defence on May 11, 2012 that an LRAD would be deployed in London during the Olympics. It was spotted fixed to a landing craft on the Thames.[69]

Mass notificationEdit

United StatesEdit

Menlo Park and Atherton, CA police and fire officials attended a 'sound off' between a siren installation and an LRAD 360XT mobile voice mass notification system in April 2018. "The side by side test was very helpful and everyone agreed that the LRAD system completely outperformed the older siren system," said Fire District Emergency Manager Ryan Zollicoffer. "Not only because of the voice capability, but the modular-mobility benefit is something that appeals to first responders because it can be used for a variety of public safety purposes and better moved around if that's needed or desired."[70]

The Menlo Park Fire District demonstrated its Long Range Acoustic Device (LRAD) community notification system on April 18, 2019. The fire district also showed how the ShakeAlert system could eventually be tied together with its LRAD to provide area wide audible alerts for earthquake, flood, fire and other emergencies. “ShakeAlert will notify and protect our Station firefighters, but we also believe coupled with the LRAD public address system, it can help to bridge the ‘notification gap’ as another important public safety tool and option for community early warning messaging for earthquakes as well as for fire and flooding information and evacuation signaling," said Fire Chief Harold Schapelhouman.[71]

The City of Laguna Beach, CA installed LRAD speaker sirens in 2018. The systems alert the downtown and Main Beach areas during an emergency where the public needs to take immediate action.[72]

In June 2019, Mill Valley, CA became the first city in the Bay Area to replace its sirens with LRAD community notification systems. The combined siren loudspeakers receive emergency messages via satellite and have back up batteries if the power fails.[73]

The Mill Valley Fire Department began testing its city's new LRAD installations on June 27, 2019. LRAD systems project both siren and voice recordings to alert and inform community members during large-scale disasters. The Long Range Acoustic Devices replaced siren-only systems in five Mill Valley, CA locations. "We believe that the purchase and installation of LRAD goes a long way to improve the resiliency and redundancy of our communication systems," Mill Valley Fire Chief Tom Welch said. "LRAD systems are highly effective in communicating warnings, instructions, and notifications throughout incident sites and over vast areas during life-threatening events."[74]

The City of Newport plans to spend $200,000 to replace three rusty tsunami warning sirens on the Balboa Peninsula with LRAD siren/public address systems. The LRAD systems are expected to be installed by the end of 2019.[75]

In October 2020, Laguna Beach, CA tested its expanded outdoor warning system of 13 Long Range Acoustic Devices mounted on buildings throughout the city. The solar-powered devices broadcast recorded evacuation messages in case cell service is disabled during a disaster[76]

High seas anti-piracyEdit

On November 5, 2005, the luxury cruise ship Seabourn Spirit employed an LRAD to repel pirates who attacked the vessel with rocket-propelled grenades about 115 km off the coast of Somalia.[77] The effectiveness of this device during the attack is not completely clear, but the pirates did not succeed in boarding the vessel and eventually fled.

The Liberian vessel MV Biscaglia was attacked on November 28, 2008. The security detachment aboard Biscaglia was reported to have used an LRAD device in an effort to repel attackers armed with assault rifles and rocket-propelled grenades. Following a one-sided shootout, the ship was seized and the unarmed security contractors abandoned ship leaving the ship and crew to the pirates.[78] The incident caused the usefulness of LRADs to be called into question by Lloyd's List.[79]

In January 2011, the Spirit of Adventure, a cruise ship sailing through the Indian Ocean, deployed an LRAD system as part of its defensive measures when being pursued by pirates.[80]

S/Y Hideaway used an LRAD in 2016 to deter suspected pirates in the Gulf of Aden.[81]

Major usersEdit

See alsoEdit


  1. ^ a b Kesslen, Ben (22 May 2019). "Plug your ears and run". NBC News. Retrieved 7 June 2020.
  2. ^ "Long Range Acoustic Device Industry Applications - Public Safety & Security Solution". Lradx.com. Retrieved 26 June 2019.
  3. ^ "Crowd Control with Long Range Acoustic Devices Can Cause Permanent Hearing Loss". Academy of Doctors of Audiology. Retrieved 13 September 2021.
  4. ^ Corbett, Peter (2009). A Modern Plague of Pirates. p. 65. ISBN 978-0-9562107-0-8.
  5. ^ "LRAD Genasys Public Safety Notification Systems Archives". Lradx.com. Retrieved 26 June 2019.
  6. ^ Beranek, Leo L. 1986. Acoustics, p.132, American Institute of Physics.
  7. ^ a b Blackstock, David T. 2000. Fundamentals of Physical Acoustics, p.456, John Wiley and Sons.
  8. ^ a b Bondy, Halley (30 September 2019). "How the LRAD Went From a Pirate Deterrent to a Police Crowd-Control Tool". The Daily Beast. Retrieved 7 June 2020.
  9. ^ a b "Acoustic Weapons Fact Sheet". www.aclu.org. Retrieved 7 June 2020.
  10. ^ ABC News. Technology & Science. August 25, 2004. Amanda Onion. RNC to Feature Unusual Forms of Sound: Unusual Forms of Sound to Emanate From RNC
  11. ^ Urbina, Ian (24 September 2009). "Protesters Are Met by Tear Gas at G-20 Conference". The New York Times. Retrieved 26 June 2019.
  12. ^ thetwos. YouTube.
  13. ^ Martin, Adam (25 October 2011). "Occupy Oakland's Tent City Is Gone". The Atlantic Wire. Retrieved 26 October 2011.
  14. ^ "Occupy Wall Street: Police use military megaphone to amplify their point to protesters". New York Daily News. New York. 18 November 2011. Retrieved 15 February 2015.
  15. ^ "As it Happens: NATO in Chicago". NBC Chicago.
  16. ^ Bill Mich (8 October 2013). "Salisbury Police Utilizing New LRAD System". Wboc.com.
  17. ^ "DAY FIVE WRAPUP: McCulloch blasts Nixon for replacing St. Louis County Police control". St. Louis Post-Dispatch. August 14, 2014.
  18. ^ [1][dead link]
  19. ^ "Video: NYPD Uses Military-Grade Sonic Weapon on Eric Garner Protesters". Alternet.org.
  20. ^ Tom O'Dare (19 March 2015). "Myrtle Beach police going high-tech for Bikefest". Myhorrynews.com.
  21. ^ NYPD LRAD warning message for protesters 4.29.15. YouTube. 29 April 2015.
  22. ^ Justin Davis. "Police Deploy Tear Gas on Crowds Outside of Hot 97's Summer Jam - Complex". Complex.com.
  23. ^ Benjamin F. Powell (5 November 2015). "GDP: New Long Range Audio Technology Could Save Lives". Wfmynews2.com.
  24. ^ "Police order anti Trump protesters to disperse". YouTube.
  25. ^ Enzinna, Wes. "I Witnessed Cops Using Tear Gas, Rubber Bullets, and Sound Cannons Against Anti-Pipeline Protesters". Motherjones.com. Retrieved 7 November 2016.
  26. ^ Ted Hart (21 November 2016). "CPD demonstrates new crowd control device". Nbc4i.com.
  27. ^ "Records show D.C. Police used an LRAD sound cannon to "direct crowd flow" during the Women's March". Muckrock.com. Retrieved 26 June 2019.
  28. ^ Henry Culvyhouse (17 February 2017). "UMES concert canceled due to unruly crowd". Delmarvanow.com.
  29. ^ Ashley Tressel (18 April 2017). "New loudspeaker ensures MCSO will be heard loud and clear". Ukiah Daily Journal.
  30. ^ "Phoenix police pick up approval, $95K for long-range, crowd-control speakers". Ktar.com. 10 November 201.
  31. ^ WROC Staff (19 August 2019). "Dozens arrested after Puerto Rican Festival". RochesterFirst.com.
  32. ^ "Protest in Phoenix over death of George Floyd ends in arrests, property damage". YourValley.net.
  33. ^ "Video of protest with LRAD use". Twitter.com. Retrieved 4 June 2020.
  34. ^ "Portland Mayor Ted Wheeler holding news conference about continued protests: Watch live". 5 June 2020.
  35. ^ KEX, 1190. "Police Use Acoustic Device On Crowd". 1190 KEX Radio. iHeart Media. Retrieved 6 June 2020.CS1 maint: numeric names: authors list (link)
  36. ^ "What is LRAD? PPB explain their 'sonic tone' device/". KOIN.com. 6 June 2020.
  37. ^ https://www.seattle.gov/documents/Departments/OPA/ManagementAction/2020OPA-0741_2021COMP-0032_MAR_06-09-21.pdf
  38. ^ https://www.seattle.gov/documents/Departments/OPA/ClosedCaseSummaries/2020OPA-0741ccs053121.pdf
  39. ^ Elijah, Koerri (August 24, 2020). "Livestream of 24 August 2020 Jacob Blake Protests". Facebook. Timestamp 2:06:56. Retrieved August 25, 2020.
  40. ^ WGN TV (August 24, 2020). "Scenes from Kenosha after shooting of Jacob Blake". Facebook. Timestamp 0:37:55. Retrieved August 25, 2020.
  41. ^ "Kenosha Courthouse Protest". Twitter.com. Retrieved 26 August 2020.
  42. ^ "Police use 'sound cannon' at Rochester protest; RPD says officers were hit with bottles, eggs". DemocratandChronicle.com.
  43. ^ "Protesters arrested outside Rochester City Hall as police break up occupation". DemocratandChronicle.com.
  44. ^ "US military police 'sought use of heat ray' to disperse White House protesters". The Guardian. September 17, 2020.
  45. ^ Savannah Behrmann (September 17, 2020). "National Guard major: Military police asked about using 'heat ray' against DC protesters". usatoday.com.
  46. ^ "Protesters Were Supposed To Hear Warnings Before Federal Police Moved In. They Didn't". npr.org.
  47. ^ Julia Tullos (September 22, 2020). "Cuyahoga County Sheriff makes changes after May 30 riot in Downtown Cleveland". Cleveland19.com.
  48. ^ Jonathan Choe (November 5, 2020). "Use of LRAD speaker by Seattle police for crowd control spurs questions, concern". komonews.com/.
  49. ^ "University Hill Disturbance Update". Boulder Police Department.
  50. ^ "Long Range Acoustic Device (LRAD) deployed in front of #BLM crowd at Brooklyn Center, MN". mehabe.com/.
  51. ^ "Long Range Acoustic Device (LRAD) deployed in front of #BLM crowd at Brooklyn Center, MN". Disclose.tv.
  52. ^ "Wakefield police used sonic blast, a high-pitch alarm, to incapacitate Rise of the Moors suspects". masslive. 2021-07-13. Retrieved 2021-07-13.
  53. ^ "Archived copy". Archived from the original on 2015-06-29. Retrieved 2015-06-27.CS1 maint: archived copy as title (link)
  54. ^ "Do Brna se kvůli demonstracím sjeli policisté ze Speciálních pořádkových jednotek z celé republiky". Policejnidenik.cz (in Czech). June 26, 2015.
  55. ^ Týdeník Policie (18 November 2020). "V centru Prahy proběhlo k výročí 17. listopadu několik shromáždění i pochodů. Nejproblematičtější byl ten proti vládním opatřením". tydenikpolicie.cz.
  56. ^ FM-Mediaservice (6 November 2020). "LRAD 100X, flexibel, kraftvoll und höchste Verständlichkeit". feuerwehrmagazin.de.
  57. ^ "Επίδειξη συστήματος LRAD για αντιμετώπιση όχλων σε Ένοπλες Δυνάμεις και Σώματα Ασφαλείας". Δούρειος Ίππος. 2020-03-13. Retrieved 2020-09-27.
  58. ^ StavrosKaripidisPage (2020-09-26). "Ηχητικά υπερόπλα στήνονται στα σύνορα του Έβρου από την ΕΛΑΣ σε συνεργασία με τον Στρατό (Και 4 νέα Drone)". Νέα, Ειδήσεις, Εκδηλώσεις στην Ξάνθη (in Greek). Retrieved 2020-09-27.
  59. ^ "Japan coastguard expels North Korean fishing flotilla". Ftchinese.com.
  60. ^ Darby, Andrew (February 6, 2009). "Whalers attack activists at sea". The Age. Melbourne.
  61. ^ Sea Shepherd Conservation Society USA. "Video - Operation Waltzing Matilda". Operation Waltzing Matilda - Sea Shepherd Conservation Society. Archived from the original on 2010-01-03.
  62. ^ Sea Shepherd Battles Japanese Whalers in the Ross Sea - Sundance Channel, 7 February 2009
  63. ^ "Street Fight on the High Seas". The New Yorker. 2010-01-12. Retrieved 2010-01-16.
  64. ^ "Ride Of The Valkyries: Japanese Whalers Claim Sea Shepherd Harasses The Nisshin Maru With Classical Music". Underwatertimes.com. Tokyo. February 9, 2010. Retrieved January 1, 2011.
  65. ^ "Potężna broń służy jako zwykły głośnik. Policyjny system LRAD pod lupą prokuratury". Rmf24.pl (in Polish). 9 January 2013.
  66. ^ krakow.wyborcz (25 March 2020). "Radiowóz z nagłośnieniem jeździ po Krakowie. Emituje apel o pozostanie w domach". krakow.wyborcza.pl.
  67. ^ Mak Źródło (22 March 2020). "Radiowozy z głośnikami na ulicach". tvn24.pl/.
  68. ^ TeleMadrid (19 March 2020). "La Policía de Leganés lanza mensajes de voz a sus vecinos con un super altavoz". telemadrid.es.
  69. ^ "'Sonic weapon' deployed in London during Olympics". BBC News. 12 May 2012. Retrieved 11 May 2012.
  70. ^ Susan C. Schena (20 April 2018). "Siren vs. Voice: Mass-Evacuation Systems Tested". Menlo Park-Atherton, CA Patch.
  71. ^ CONTRIBUTED CONTENT (18 April 2019). "Menlo Park Fire demonstrates early warning system for earthquakes and other natural disasters". inmenlo.com/.
  72. ^ "Tsunami Awareness Week 2018". lagunabeachcity.net.
  73. ^ Cornell Barnard (27 June 2019). "'It's loud!' Mill Valley installs new emergency warning system". abc7news.com/.
  74. ^ Kristina Houck (27 June 2019). "Mill Valley To Test New Emergency Sirens". patch.com/.
  75. ^ Hillary Davis (20 August 2019). "Newport Beach to replace rusty tsunami warning sirens". Los Angeles Times.
  76. ^ Daniel Langhorne (30 October 2020). "Laguna Beach's wildfire mitigation plan still a work in progress". lagunabeachindy.com/.
  77. ^ "I beat pirates with a hose and sonic cannon". BBC News. May 17, 2007. Retrieved May 11, 2010.
  78. ^ "Login". Timesonline.co.uk.
  79. ^ David Osler, (2 December 2008). "Sonic solution may not be a sound investment", Lloyd's List. London: Informa. Retrieved 13 April 2011.
  80. ^ Sloan, Gene (January 17, 2011). "Cruise ship blasted pirates with sonic wave". USA Today. Retrieved July 17, 2011.
  81. ^ William Bruton (February 2017). "Standoff". Dockwalk.com.
  82. ^ Australian police authorities buying up sound weapons, The Law Report, ABC Radio, May 17, 2016
  83. ^ This Pain-Inducing Acoustic Device Used to Control Crowds in Azerbaijan Might Be U.S.-Made, The Atlantic, March 14, 2013
  84. ^ "La police de Montréal se dote de canons à son". La Presse. 22 May 2014.
  85. ^ Premiéra akustické zbraně v Opavě. Šéf policie: Odvedli jsme excelentní práci, Deník.cz (in Czech), March 19, 2017
  86. ^ Calayag, Third Anne Peralta-Malonzo and Keith (14 November 2017). "Riot police level up defense with sonic weapon". Sunstar. Retrieved 26 June 2019.
  87. ^ "MaxDefense Philippines". Facebook.com. Retrieved 26 June 2019.
  88. ^ CSIR confirms legality of using LRAD units, EWN, September 1, 2016
  89. ^ [=http://www.eldiario.es/politica/Centenares-personas-recorren-Madrid-Gamonal_0_219078935.html El Diario : News : Los mossos utilizan un cañón de sonido para dispersar a los manifestantes en Barcelona]
  90. ^ "Möte med lokala fiskare – Operation Atalanta". blogg.forsvarsmakten.se. Retrieved 26 June 2019.

External linksEdit