BISMARCK, N.D. -

North Dakota authorities are sending officers from across the state to the site of a protest in anticipation of a federal judge's ruling on a request by the Standing Rock Sioux to block construction of a four-state oil pipeline.

U.S. District Judge James Boasberg is expected to rule Friday on the tribe's request to temporarily stop construction on the Dakota Access pipeline.

The Morton County Sheriff's Office said Wednesday in a statement that it's "preparing and planning for all scenarios that may occur in response to the federal court ruling." The statement didn't say how many officers were being added.

No law enforcement personnel were present Saturday when violence broke out between private security guards and protesters. Authorities say the crowd dispersed when officers arrived and no one was arrested.