Flames shot into the sky at Tulsa's Holly Frontier Refinery Tuesday, but it wasn't an emergency.
It was an important learning opportunity for firefighters. The Tulsa Fire Department along with Sand Springs and Broken Arrow teamed up with Holly to learn how to fight fires fueled by flammable liquids.
It's good hands-on experience for the pros and required training for cadets.
"In that is flammable liquids, some haz mat…all types of training we have to do, and we have to fulfill each one of those in order for them to be certified," said Captain Stan May, with the Tulsa Fire Department.
Crews attacked the fuel oil fire with water and hose lines, rather than foam, so they can practice proper techniques.