Officials in Southern California are warning residents to stay clear of beaches as a 13-mile-long oil spill is about to wash ashore

• A pipeline leak is believed to be the cause of an oil spill, The Los Angeles Times reported.
• The 13-mile spill is off the coast of Newport Beach and Huntington Beach in Southern California.
• The spill is expected to come ashore sometime Saturday night and officials warned against swimming.

City officials in the city of Newport Beach, California, are warning residents not to swim at beaches after a large oil spill reported off the coast is expected to come ashore sometime Saturday night.

The Los Angeles Times reported that the 13-mile slick is believed to have originated from a pipeline leak. The spill stretches between Newport Beach and Huntington Beach.

Huntington Beach city officials also closed their beaches starting at around 7 p.m. local time.

In a tweet, officials said they are closely monitoring the situation.

Kate Conrad of Beta Offshore, a Southern California oil producer, told the Times that the incident was reported around noon on Saturday and workers shut down the pipeline soon after. Crews also used pressurized equipment to retrieve oil, KABC reported.

The Coast Guard also said it was responding to the spill, as did California's Department of Fish and Wildlife in a tweet on Saturday afternoon.

CDFW did not respond to Insider's request for comment but spokesman Eric Laughlin told the Times that people shouldn't approach affected wildlife as it could cause more harm than good.

"Members of the public should avoid the oiled shoreline, as the area is unsafe and should only be cleaned by trained contractors," Laughlin told the Times.