Authorities say they have begun taking steps to remove Dakota Access pipeline protesters camped on private land in the path of the pipeline in North Dakota.
The Morton County Sheriff's office says law enforcement began the operation at 11:15 a.m. local time Thursday, a day after protesters refused to leave voluntarily.
About 200 activists supporting the Standing Sioux Tribe moved onto the site last weekend, setting up teepees and tents and saying the land is rightfully theirs under a more than century-old treaty.
But the pipeline's developer, Texas-based Energy Transfer Partners, says the protesters are trespassing and demands they leave.
The almost-complete $3.8 billion pipeline passes through North Dakota, South Dakota and Iowa to Patoka, Illinois. Opponents worry about its negative effect on drinking water, as well as the potential destruction of cultural artifacts
More than 260 people have been arrested since demonstrations began in August.
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