LONG BEACH (CBSLA.com) About 30,000 customers went without power following an outage Thursday afternoon in Long Beach.

The outage was blamed on an underground vault fire.

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Officials with Southern California Edison are investigating the exact cause of the outage which was reported just before 4:15 p.m.

Initials report said about 1,000 were without power but officials increased the affected grid. Hours later, at a news conference around 8 p.m., officials said power had been restored to all but about 1,000 customers.

By 10:30 p.m., officials said only about 400 customers were still without power.

(credit: the city of Long Beach)

(credit: the city of Long Beach)

Officials told CBS2/KCAL9 that power for some could be out until Friday.

The outage continues and is limited to Pacific Boulevard to Long Beach Boulevard and 14th Street to 7th Street, said SCE.

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It was the second major outage to hit the area in a two week period. A vault explosion in that same area knocked out power for days.

No injuries have been reported.

City officials asked that all residents and visitors be mindful of their activities.

Mayor Robert Garcia also asked residents to be mindful of neighbors, seniors, and children.

Officials also announced the opening of a shelter for residents who remained without power: A shelter will open at 11 p.m. at Cesar Chavez Park, 4th and Golden.

Garcia told KCAL9’s Erica Nochlin the second power outage is “unacceptable.” He also said he spoke to scores of angry residents. And he said he didn’t blame them for being upset.

“They’re frustrated,” he said “and I don’t blame them. I’m frustrated, too. We’re getting generators to senior buildings and we’re just trying to help people as best we can and that’s what we’ll do now.”

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