North Dakota has officially removed all protesters from the main Standing Rock camp after police swept through Thursday and arrested 47 people.

Officers walked into the camp wearing riot gear, driving military vehicles and carrying guns. Nearby a sign in the camp stated “we are unarmed.” After they arrested the remaining protesters, bulldozers began tearing down the last structures. The Morton County Sheriff’s Department said the ammunition in the guns was “most likely lethal.”

The arrests mark the end of the main protest camp, Oceti Sakowin, which swelled to an estimated 10,000 people in November, but contained only about 70 people on Thursday.

Since the protest began 11 months ago, the region’s Indigenous people and allies have gathered at the site in North Dakota to resist the Dakota Access Pipeline, which they say has destroyed sacred sites, violated treaty rights and is likely to contaminate drinking water downstream.

North Dakota’s governor Doug Burgum had originally set a deadline of 2 p.m. Wednesday for all protesters to leave the camps or they would be evicted. The order followed a request in January by the Standing Rock Sioux Tribe for protesters to pack up and leave the land, partly because Tribal Chairman Dave Archambault II had said the tribe’s battle is now in the courts, and because the camps are on a floodplain that is expected to flood in the spring.

Protesters have moved to other camps, including the Sacred Stone camp, which was not evicted and is not on the floodplain.

Officers who swept the camp on Thursday came from North Dakota, Indiana, Wisconsin, Georgia and Alabama, police told VICE News.

Ten people were arrested Wednesday evening on Highway 1806, including one journalist. Charges ranged from “obstruction of a government function” to “resisting arrest.” Also on Wednesday, the protesters, who call themselves water protectors, set fire to several structures in what they called a cleansing ritual.