WASHINGTON, D.C. (Press Shia) – A group of Native Americans, civil and peace activists, and ordinary American citizens held a rally in Washington, D.C., to protest against the Dakota Access oil pipeline, a project they say threatens water supplies and sacred Native American sites.

The demonstration was held on Pennsylvania Avenue, at the invitation of Native Americans residing in Washington, D.C., Virginia and Maryland.

The protesters then marched to Washington Monument, holding placards in support of the Standing Rock campaign.

Native Americans have launched the campaign to prevent the construction of the controversial oil pipeline near the Standing Rock Indian Reservation in North Dakota.

Completion of the $3.7 billion Dakota Access Pipeline, set to run 1,172 miles (1,885 km) from North Dakota to Illinois, was delayed in September so federal authorities could re-examine permits required by the Army Corps of Engineers.

The Standing Rock tribe and environmental activists say the project would threaten water supplies and sacred Native American sites and ultimately contribute to climate change. Protests have at times turned violent, as security dogs attacked activists during the rallies.