Dakota Access oil pipeline protesters defy law enforcement officers who are trying to force them from a camp on private land in the path of pipeline construction Oct. 27. (James MacPherson/AP)

Activists protesting the Dakota Access oil pipeline say police marked them with numbers and held them in “dog kennels” after authorities last week cleared a camp of demonstrators from private property in Cannon Ball, N.D., and took 141 people into custody.

In a YouTube video posted Friday, Floris White Bull said she was arrested and transported by bus to the Morton County Correctional Center, where she and other arrestees were locked in cages in the facility’s garage.

“We were caged in dog kennels and sat on the floor and we were marked with numbers,” she said. “My mind, I couldn’t wrap it around the fact that this is happening today. This isn’t something that we’re reading in history books.”

Several other activists gave similar accounts and shared photos of numbers scrawled on their skin in black marker.

Protest organizer Mekasi Camp-Horinek said after he and his mother were arrested, police placed them in one of the metal enclosures together and wrote a number on his arm. He told the Los Angeles Times that there was no bedding or furniture in the cage.

“It goes back to concentration camp days,” Camp-Horinek said.

The Morton County Sheriff’s Department said in a statement that the enclosures were “temporary holding cells” made out of chain link fence and were used only when police made mass arrests, as was the case Thursday. The cells are approved by the North Dakota Department of Corrections, and prisoners have access to bathrooms, meals and drinking water, the department said. The Morton County Correctional Center, where many of the prisoners were transported, has room for 42 inmates at a time.

Morton County spokesman Rob Keller told the Bismarck Tribune that police used numbers to keep track of personal property when they were released from jail.

A Reuters reporter tweeted images Monday of what he said were the cells.

The 1,172-mile pipeline is slated to carry oil from North Dakota through the Midwest to Illinois, where it can be sent to refineries. The Standing Rock Sioux and other Native American tribes say a portion of the pipeline threatens to pollute their only drinking water supplies and disrupt cultural lands. Energy Transfer Partners, the developer, and North Dakota officials say the pipeline is safe and would not harm cultural sites.

For months, activists have used a camp on federally owned land to stage demonstrations against the $3.8 billion project, which is close to completion in North Dakota. Last week, some protesters attempted to set up another encampment on private property nearby, using vehicles, scrap wood and bales of hay to barricade roadways in the area. Authorities moved in with trucks and military Humvees when protesters refused to leave, using pepper spray, rubber bullets and high-pitched noise cannons to disperse the crowd of several hundred. Some protesters set fires along the road and threw rocks and Molotov cocktails at authorities, while others on the scene prayed and passively resisted.

During the confrontation, one protester allegedly opened fire on sheriff’s deputies, nearly striking one, authorities said. The suspect, Red Fawn Fallis, was arrested and charged with attempted murder, according to a statement Sunday from the sheriff’s office.

By Thursday night, police had taken 141 protesters into custody, according to the sheriff’s office.

Late Saturday afternoon, all of them walked free when an anonymous donor paid $2.5 million to have them released, News On 6 reported.

Tribal leaders have criticized the response from law enforcement, saying more than 40 people were injured by pepper spray and bean bag rounds fired by authorities while others were humiliated by their treatment while in custody. Standing Rock Sioux Chairman Dave Archambault II said he is considering a class-action lawsuit against law enforcement, the Bismarck Tribune reported.

“The best way for success is to go after every individual law enforcement who fired a weapon at innocent people,” he said. “We have to get badge numbers. We have to get facial recognition. We have to get these law enforcement that are from other states, whoever it is. And individuals who are harmed have to report what has happened.”

Archambault has also called for the U.S. Department of Justice to investigate the tactics used by authorities.

“DOJ can no longer ignore our requests,” Archambault said in a statement. “If harm comes to any who come here to stand in solidarity with us, it is on their watch.”

Cheyenne River Sioux Chairman Harold Frazier said he was alarmed when he found out people were marked with numbers after being arrested.

“It’s really sad,” he said. “Their rights obviously have been violated.”

On Sunday, Edward John, a representative from the United Nations Permanent Forum on Indigenous Issues, visited the main camp in Cannon Ball, N.D., to hear protesters’ concerns, the Tribune reported. The forum tends to meet only annually, he said, “but this is an extraordinary situation.”

Law enforcement officials said they used restraint throughout the confrontation, and only advanced on the camp after promising not to make arrests if protesters left on their own accord.

North Dakota Highway Patrol Capt. Brian Niewand said his officers used force sparingly and tried to arrest only those who attacked authorities or refused to leave the area, according to the Tribune.

“Showing that respect for all the people that are out there, whether they are white, black, Native American, it doesn’t matter, we respect everybody,” he said in a news conference Friday. “The actions of some caused us to have to use force in certain circumstances, which was very, very unfortunate.”

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