Officers in riot gear arrest 28 in violent clashes with North Dakota pipeline protesters

Twenty-eight protesters against the Dakota Access oil pipeline were arrested west of Mandan, N.D., during a day in which activists held demonstrations nationwide.

Morton County sheriff's spokesman Rob Keller says about 400 protesters put a pickup truck and tree branches on BNSF Railway tracks Tuesday near a pipeline work staging area. The railroad says trains were delayed three hours.

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Officers in riot gear used pepper spray and in one instance a stun gun against protesters who refused to leave.

Activists called for demonstrations at Army Corps of Engineers offices and at banks financing the pipeline construction. Protests were reported across the country, from California to Vermont.

Mandan is about 80 kilometres north of a camp where hundreds of protesters have gathered in recent months to oppose the $3.8-billion pipeline that's to carry North Dakota oil to a shipping point in Illinois. 

Opponents say it poses a threat to sacred Indigenous land, and to the Missouri River, which is the main water supply for the nearby Standing Rock Sioux Tribe reservation.

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