Fatal blast rocks Oklahoma refinery

One person is killed and another injured after a refinery blast in Wynnewood Friday evening.

Garvin County Sheriff's Office tells KRMG it happened around 6:30 p.m. at the Wynnewood Refinery, an hour South of Oklahoma City.

It's believed the explosion occurred because of a build up of gases at a unit.  Deputies say it occurred during a 'turnaround time" at the plant.  This is when maintenance is performed at the facility which happens every four years.

Family members have been notified of the death, but the name of the deceased hasn't been released yet.

The refinery is owned by CVR Energy and will remain open during the investigation.