MOUNT CARBON, W.Va. (AP) – Fires burned for hours after a train carrying more than 100 tankers of crude oil derailed in a snowstorm in West Virginia, plunging at least one tanker into a river while sending a fireball skyward, authorities and residents say.

Federal railroad and hazardous materials officials are probing Monday’s derailment. One person was treated for potential inhalation issues, but no other injuries were reported, the train company CSX said in a statement.

The office of Gov. Earl Ray Tomblin said the tanker cars were loaded with Bakken crude from North Dakota and headed to Yorktown, Virginia.

Officials evacuated hundreds of families and shut down two water treatment plants threatened by oil seeping into the river. Authorities say fire crews opted to let the tanker cars burn themselves out.