The Standing Rock Sioux Tribe filed an emergency motion Sunday for a temporary restraining order "to prevent further destruction of the tribe's sacred sites by Dakota Access Pipeline," it said.
"On Saturday, Dakota Access Pipeline and Energy Transfer Partners brazenly used bulldozers to destroy our burial sites, prayer sites and culturally significant artifacts," Tribal Chairman David Archambault II said.
"They did this on a holiday weekend, one day after we filed court papers identifying these sacred sites. The desecration of these ancient places has already caused the Standing Rock Sioux irreparable harm. We're asking the court to halt this path of destruction."
The pipeline's developer, Energy Transfer Partners
, has defended the $3.7 billion project, saying it would help the United States become less dependent on importing energy from unstable regions of the world.
What the tribe wants
The tribe wants to halt further construction on an area 2 miles west of North Dakota Highway 1806, near Lake Oahe, until a judge rules on its previous motion to stop construction, the tribe said.
That motion is based on the plaintiffs' claim that it was not properly consulted before the US Army Corps of Engineers approved the pipeline project, which would run from North Dakota to South Dakota, Iowa and Illinois.
A US district court judge is expected to make a decision on the case by Friday. The Army Corps of Engineers has declined to comment, citing the pending litigation.
Thousands of people from more than 200 Native American tribes have supported the Standing Rock Sioux's efforts to protect their lands, waters and sacred sites during construction of the 1,200-mile pipeline, the tribe said.
What the pipeline would do
If completed, the 1,172-mile pipeline would carry 470,000 barrels of crude oil a day from North Dakota to Illinois.
Energy Transfer said the pipeline would bring an estimated $156 million in sales and income taxes to state and local governments. It would also add 8,000 to 12,000 construction jobs, the developer said.
But about 30 environmental groups, including the Sierra Club and Greenpeace, have slammed the pipeline project
, calling it "yet another example of an oil pipeline project being permitted without public engagement or sufficient environmental review."'
Protesters are also worried that digging the pipeline under the Missouri River could affect the drinking water supply if the pipeline breaks.
Sheriff: Protests turned violent
Protests against the pipeline turned violent in North Dakota over the weekend, with some demonstrators breaking down a wire fence and trespassing onto a construction area, the Morton County Sheriff's Department said.
"Protesters physically assaulted private security officers hired by Dakota Access Pipeline. The security officers were hit and jabbed with fence posts and flagpoles," the sheriff's department said.
"According to several reports from security officers, knives were pulled on them or they witnessed protestors with large knives." The sheriff's department also said two guard dogs were injured.
But protesters disputed the authorities' account, CNN affiliate KFYR
said. Demonstrators said the guards sprayed many of the activists with pepper spray and tear gas, and some protesters were injured by the guards' dogs.
"It was kind of scary," Lonnie Favel told KFYR. "A lot of people are out here with their children. Accidents happen all the time with dogs, and people could really get hurt."