“The cause of the blaze was not clear,” the Los Angeles Times said, while broadcaster CBS said officers and firefighters rushed to the refinery in Los Angeles county after reports of an explosion.

“Our office is coordinating with local and state agencies to … ensure public safety,” Newsom’s press office said on X.

CBS cited police as saying they were not aware of any immediate injuries or evacuations, adding that Los Angeles county supervisor Holly Mitchell had said crews contained the fire to one area of the refinery.

In a regulatory filing, the US energy major also reported emergency flaring at El Segundo.

The refinery’s rated capacity is 290,000 barrels per day, and its main products are gasoline, jet and diesel, Chevron says on its website.

Its total storage capacity is 12.5 million barrels in about 150 major tanks.

“The Los Angeles fire department is ready to assist with any request for aid,” Mayor Karen Bass said.

“There is no known impact to LAX at this time,” she added referring to the city’s busy international airport.