Officials are "strongly recommending" that residents of Casselton, N.D., evacuate following an oil train derailment and fire west of town.
The Cass County Sheriff's Department says anyone five miles to the south or east of town should also go somewhere safe until further notice.
A shift in the wind could create health hazards by blowing smoke from the train fire closer to town, a sheriff's department spokesperson said in a statement.
The Red Cross and Salvation Army have organized a shelter for evacuees at Discovery Middle School in Fargo.
Anyone who needs a ride is asked to contact Cass County Tactical Operations Center at (701) 297-6000.
Cass County sheriff's department spokesperson Sgt. Tara Morris estimates about 10 cars from a mile-long train caught fire and will have to burn out. She said it could take up to 12 hours before authorities can get close.
No injuries have been reported to the sheriff's department. The derailment apparently triggered an explosion that sent a fireball hundreds of feet in the air. The accident happened a mile outside of Casselton. The town of 2,400 people is about 25 miles west of Fargo.
BNSF Railway spokesperson Amy McBeth said a westbound train carrying grain derailed and some cars hit the train carrying crude oil, which was on another main track. Cass county authorities said the BNSF train was traveling east.
Casselton firefighters and the Fargo Fire Department's Hazardous Materials Response Team are fighting the fire.
Authorities are asking people not involved in the evacuation but who are within 10 miles of Casselton, N.D., to stay inside until further notice.