Apparent oil spill seen off popular Southern California coastline, authorities said

An oil spill appeared off the Southern California coast Thursday night, near one of the region's most popular beaches, authorities said.

The slick sheen was spotted about 1 1/2 miles off Huntington Beach in Orange County, about 40 miles southeast of downtown Los Angeles, and appeared to be about 2 1/2 miles long, the U.S. Coast Guard said.

The possible oil spill was first reported about 6:50 p.m. Thursday, the Coast Guard said.

"We are actively monitoring reports of an oil sheen near Huntington Beach," Gov. Gavin Newsom said in a statement. "We have deployed personnel to evaluate the incident and will continue to coordinate with local, state and federal partners. "

It wasn't immediately unclear if the slick came from a vessel or leaked from a nearby oil platform.

The sheen is far enough off the beach that swimmers and surfers were still safe, Friday, officials said.

Containment booms and absorbing material have been placed around the slick and appear to have controlled any expansion or movement, USCG Petty Officer Richard Uranga said.

"It really wasn't spreading too much, it wasn't increasing from when it (first) appeared," Uranga said.

Beta Operating Company runs oil platforms off the coast of nearby Long Beach. But parent company Amplify Energy said it does not believe this slick is linked to its operations.

"Amplify Energy Corp. is aware of reports of an oil sheen off the coast of Huntington Beach, California. At this time, we have no indication that this sheen is related to our operations," the Houston-based company said in a statement. "We will continue to cooperate with the U.S. Coast Guard and other relevant authorities and provide support in any way we can."