INDIANAPOLIS — Protesters opposed to the four-state Dakota Access oil pipeline are rallying in downtown Indianapolis.

Group members are marching in solidarity with Native Americans fighting to stop the pipeline that would run from North Dakota to Illinois. The group in Indianapolis marched on Friday to the Eiteljorg Museum of American Indians and Western Art.

A federal judge is expected to rule on the Standing Rock Sioux tribe’s request to block the $3.8 billion pipeline over environmental concerns.

The Standing Rock Sioux tribe says the pipeline threatens their drinking water and has disturbed sacred sites.

An association made up of tribal leaders in the Dakotas and Nebraska has asked U.S. Attorney General Loretta Lynch to send federal monitors to the site of a large protest in North Dakota.