Flames lit up a dark sky in Tulsa, Oklahoma after an explosion and fire in a refinery.

The explosion and blaze caused one smokestack to collapse, according to local radio station KRMG.

No injuries have been reported and the cause of the explosion was not clear.

The company's fire crews contained the fire and allowed it to burn out as Tulsa Fire Department was put on stand-by.

A company representative from Holly was not available for comment on the blaze.