Fire crews are battling a blaze at BP Plc's Cherry Point refinery in Ferndale, Washington, Friday afternoon, the oil company said.
"The fire is reportedly in a tower on the south side of the refinery," the Bellingham Herald said on its website.
BP spokesman Scott Dean said it was too early to tell where the fire was in the refinery but there were no reports of injury.
A plume of heavy black smoke is visible for several miles at about 2:30 pm local time on Friday, the reports said.
The refinery has its own fire crews but mutual aid had been requested from Whatcom County Fire District 7 in Ferndale and other agencies, the website noted.
Cherry Point can refine 225,000 barrels of crude oil per day and is the largest oil refinery in Washington.
