The oldest Dakota Access Pipeline protest camp was emptying out on Tuesday after federal agents ordered people to disperse, saying they were trespassing on Native American land in North Dakota.

Bureau of Indian Affairs agents issued a Feb. 27 deadline for people to leave the Sacred Stone camp and other sites on the Standing Rock Sioux reservation. Tribal officials said the camps weren’t authorized, though the tribe had welcomed protesters for months.

A BIA spokeswoman told HuffPost that agents distributed notices to about 200 people, warning that campers were “directed to vacate the property immediately.”

It was unclear how many pipeline protesters, who call themselves “water protectors,” remained on Tuesday. Reports from independent media showed protesters packing up and preparing to leave.

BIA spokeswoman Nedra Darling told HuffPost that agents did not plan raids like the ones carried out by North Dakota law enforcement last week at what had been the largest protest camp. In those crackdowns, officers in riot gear and armored vehicles confronted several hundred holdouts at Oceti Sakowin camp and arrested more than 80 people in two days.

The Standing Rock Sioux had supported the resistance camps for months and encouraged protesters to join their fight against the 1,172-mile pipeline. The tribe and its supporters say the pipeline was not reviewed properly for environmental hazards and violates an 1851 treaty with the federal government. An unfinished section of the pipeline would threaten the reservation’s drinking water, the tribe says.

Sacred Stone was the first camp to spring up, in April. Organizer Laddona Allard told HuffPost last month that it was a family-oriented camp and hoped it would become a permanent site to educate children.

“Our main focus is how do you take a negative and make it a positive,” Allard said in January. She didn’t respond to HuffPost’s inquiries on Tuesday, but criticized the tribe last month for trying to break up the camp.

Tribal officials’ attitudes toward the camps changed after the Obama administration in December said it would not grant a permit to Energy Transfer Partners to build the final pipeline section under the Missouri River near the Standing Rock reservation.

The tribe passed a resolution in January ordering water protectors to leave for reasons that included harsh winter conditions, “a vast amount of reduced revenue” at the tribe’s casino, and a shift in strategy to focus on lawsuits against the pipeline.

The BIA received a request from the Standing Rock Sioux chairman on Feb. 7 to help remove several hundred protesters remaining at the camps.

“In order to maintain order and ensure public safety” while clearing the campsites, “the Tribal Council request increased law enforcement resources on the Standing Rock Indian Reservation,” Chairman Dave Archambault said in a letter to the BIA.

A spokeswoman for Archambault declined to answer questions about the request.

Joyce Braun, another leader at Sacred Stone, expressed concern for protesters who remained at the camp in a Facebook post.

Pipeline construction has been racing toward completion after President Donald Trump this month reversed Obama’s decision to block construction near the tribe’s water source.

The Standing Rock Sioux and allies from the Cheyenne River Sioux, whose reservation is nearby, continue to fight the Trump administration in court. They recently expanded their argument to allege that the pipeline would interfere with their freedom of religion.

Energy Transfer Partners has said that the pipeline is safer than transporting oil from the Bakken region in North Dakota by train or truck. The company also says the government properly reviewed the project and was wrong to temporarily delay it last year.

A federal judge said Tuesday that he’ll decide by next Tuesday on the Standing Rock Sioux’s request to temporarily halt construction again, according to The Associated Press.