U.S. military veterans continue to arrive at the snowy Standing Rock encampment to form a human shield between protesters and police. By Sunday, camp organizers say, about 2,000 vets will be on site.

“Our goal is to stand there and if need be take the rounds for the First Nations people so they can do their thing,” said Mark Sanderson, a former Army Sergeant who served in Iraq.

The vets, who will be unarmed but wearing body armor, have vowed to protect protesters from police who have arrested hundreds of people in the last two months while utilizing tear gas, rubber bullets, and water cannons.

The Army Corps of Engineers has said that on Dec. 5 it will close the land it manages and on which the Oceti Sakowin camp stands. North Dakota’s governor has said the camp must immediately evacuate at that point, citing safety concerns now that the bitter plains winter has arrived.

“I appreciate the governor’s concern about our safety,” said Oceti Sakowin media organizer John Bigelow. “I wish he had been concerned about our safety when he was spraying us with water cannons in 23 degree weather.”

On Thursday, President-elect Donald Trump said for the first time that he endorses the $3.8 billion Dakota Access Pipeline, which protesters, who call themselves water protectors, fear will leak into water supplies and destroy sacred burial sites.

Trump’s support “has nothing to do with his personal investments and everything to do with promoting policies that benefit all Americans,” according to a communications briefing from Trump’s transition team. Trump has investments in companies that stand to benefit from the pipeline.

Protectors have refused to leave the land, and it’s unclear whether police will forcibly remove them. If they attempt to, veterans say they will be there to help.

“We’re here to assist in any way possible,” Sanderson said. “The police are trying to say it’s not a peaceful protest because we’re in body armor. But I mean, this doesn’t look aggressive at all. There are no magazine pouches, there’s nothing that can be construed as having a weapon. We’re just padding ourselves against any force they might use.”

For Sanderson, the battle over the pipeline is not just an environmental issue. He also feels that he’s standing on the right side of history after fighting in Iraq, which he says he considers an unjust war.