UPDATE at 4:20 p.m., Monday, June 1: The beaches were reopened over the weekend. More below.

Authorities on the federal, state and local levels were trying to find out how petroleum product, including “tar balls” and “tar patties,” ended up washing ashore along South Bay beaches yesterday, the U.S. Coast Guard said.

About 6.5 miles of shoreline in El Segundo, Manhattan Beach, Hermosa Beach and Redondo Beach was shut down by authorities just as many public schools were out for summer and only days after the season's traditional kickoff, Memorial Day Weekend.

Beaches were “closed from the El Segundo Jetty to the South Redondo Beach border,” and experts warned beachgoers that contact with the stuff could cause “skin irritation, headaches from the odors and other negative health effects,” according to environmental group Heal the Bay.

Los Angeles County Supervisor Don Knabe seconded that emotion, saying:

I want to encourage beachgoers to please listen to the lifeguards and obey beach closure signs. Stay out of the water and do not touch any of the material that has washed ashore, as it could be harmful if you come into contact with it.

Heal the Bay said it was “unlikely” the petroleum, which it described in a statement as “significantly sized oil blobs,” was related to the oil pipeline breach at Refugio State Beach in Santa Barbara County.

“It is simply too early to tell where the oil came from,” the nonprofit said in a statement.

Sill, officials were taking samples of the stuff to see if its origins could be determined. Authorities said early on that they didn't believe this particular petroleum was a natural product of the sea.

Booms were being installed at the mouths of King Harbor Marina and Ballona Creek as a precaution, according to the Coast Guard.

Capt. Charlene Downey, the federal on-scene coordinator for the situation, said:

Response personnel are working through the night as we continue to clean and investigate the area. Our immediate focus is on public safety and protecting the environment, and we are working diligently to try to determine the source.

The Coast Guard, the California Department of Fish and Wildlife, Los Angeles County Lifeguards, Los Angeles County Fire Department, Los Angeles Department of Public Health, the Department of Beaches and Harbors and the L.A. County Office of Emergency Management all responded to the spill.

The government entities have directed two private companies to clean up as much of the petroleum product as possible. U.S. Rep. Ted Lieu, who represents the area, said clean-up costs were being channeled through the federal government: 

The oil cleanup is being paid for by the Oil Spill Liability Trust Fund, a fact which underscores the necessity of these kinds of funds. My staff and I will continue to monitor this situation closely.

UPDATE at 4:20 p.m., Monday, June 1: The U.S. Coast Guard stated over the weekend that the beaches have been reopened:

The Unified Command continues to monitor and patrol the area. Los Angeles County Fire Department Lifeguard Division will have personnel monitoring the shoreline. Two joint agency shoreline assessment teams will patrol between Point Dume and the Torrance-Redondo Beach border Saturday and Sunday.

Cleanup crews will remain available to respond at the shoreline assessment teams direction.

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