A freight train believed to be carrying crude oil derailed in rural North Dakota Monday afternoon, creating a massive explosion.

Video taken three quarters of a mile away from the disaster near Casselton, N.D., captured the moment one of the train cars exploded.

A mushroom cloud of fire blasted into the sky and then black smoke smothered the surrounding area as the wreckage continued to burn.

Casselton Mayor Ed McConnell told ABC News the cause of the derailment was not immediately known. He said fire crews were on the scene and were waiting for the approximately 30 cars involved to burn themselves out to prevent any environmental threat from the oil.

The train consisted of 110 tanker cars, but McConnell said there were also grain cars nearby and they may have been part of the freighter.

No injuries have been reported.

Smoke from the burning cars is blowing south, away from Casselton, but McConnell said residents have been told to "hunker down" inside their homes.

ABC News' Andrew Fies contributed reporting.