William Brownotter, 16, added in a statement, “By refusing to stand against DAPL, Hillary is putting our environment, wildlife, culture, and land at risk.”

Now is the time to prove your commitment to both strong climate action and Indigenous sovereignty. Silence is not acceptable.

As police in ND seem poised to raid #NoDAPL camp, Standing Rock youth flood Clinton campaign HQ to demand she oppose Dakota Access pipeline pic.twitter.com/4ixgjiuGpk

Young activists from Oceti Sakowin, the Seven Council Fires and the Standing Rock Sioux Nation demanded that the Democratic candidate speak out against the Dakota Access pipeline , according to Greenpeace, which helped coordinate the action.

Standing Rock youth have traveled to New York for a protest at the Brooklyn headquarters of presidential candidate Hillary Clinton – on the same day that police in North Dakota have closed in on the oil pipeline demonstrators, launching a tense standoff that has dragged on for hours.

Reports are coming in that police are deploying a sonic weapon called a Long Range Acoustic Device, or LRAD.

This is a picture of the device taken on the scene, which appears to show an LRAD 500X mounted on top of the black vehicle:

#DAPL gets laid while militarized police forces use LRAD sound cannon & massive lines of riot police to clear new #OcetiSakowin camp #NoDAPL pic.twitter.com/ZXnLPkjMUR — Unicorn Riot (@UR_Ninja) October 27, 2016

The LRAD was designed as a messaging device to project sound over long distances, but they are also sometimes used for crowd control.

According the the manufacturers’ website:

LRAD fills the critical gap between the poor voice quality and limited broadcast range inherent in bullhorns and vehicle PA systems, and kinetic measures including water cannons, tear gas projectiles, rubber bullets, pepper balls, Tasers and flash bang grenades.



Also known as “sonic weapons”, LRADS are sometimes fitted to ships to repel attacks by pirates, but they are most often used by police.

LRADS were deployed during the clearances of Occupy protests in Oakland in 2011, and during the protests following the killing of Michael Brown by police in Ferguson, Missouri, in 2014, and the protests following the killing of Eric Garner by police in Staten Island, New York, the same year.

While the LRAD is designed to be non-lethal, at medium range it can cause extreme pain and at 15 meters or less it can cause permanent eardrum damage.

Updated at 14.27 EDT