CORNELIUS, Ore. (AP) — Officials say a large fire Tuesday at a Cornelius ethanol facility west of Portland was likely caused by static while employees were transferring fuel between metal drums.

Fire crews responded to the blaze about 1:30 p.m. after reports of a fuel tank on fire. The flames erupted at the Summit Foods Inc. complex, which also houses subsidiary Thunderbolt Racing Fuel, where the fire started, The Oregonian/OregonLive reported.

Crews initially worked to extinguish the fire but were pulled back to a safe distance because of “explosions and erratic fire conditions,” according to Forest Grove Fire & Rescue spokesperson Matt Johnston.

The fire also forced evacuations in the surrounding area.

Officials said that employees were transferring gasoline from one metal drum to another using an air compressor. At some point, one of the employees began feeling “intense heat” coming from one of the drums and saw flames coming from a port on the side of the container.

The employee tried unsuccessfully to put the fire out with an extinguisher.

No one was injured in the blaze, which was brought under control around 7 p.m.