LONG BEACH (CBSLA.com) — More than 3,000 Southern California Edison customers remain without power Thursday after three underground electrical vaults caught fire in downtown Long Beach.

The fires were reported about 3:40 p.m. Wednesday, and initially cut power to about 4,800 customers said. The fire initially increased underground pressure and caused manhole covers to pop off.

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Long Beach Fire Department spokesman Jake Heflin said the vaults were beneath the 400 block of Third Street, and near the intersections of Pacific Avenue and 9th Street, and Pine Avenue and Nardo Way.

Some nearby residents briefly were evacuated, Heflin said.

No injuries were reported from the fires, but the outage left large residential areas adjoining downtown businesses without power overnight.

Spokesman Paul Grigaux says utility workers hope to have power mostly restored overnight but some customers could be without electricity well into Friday.

About 10 a.m., authorities announced that restoration of service would require intermittent shutting off of all electricity for varying periods of time within substations in various parts of the following area: Cherry Avenue to the east, Willow Street to the north, the Long Beach (710) Freeway to the west, and Shoreline Drive to the south.

The work to restore service was “moving forward” throughout the affected power grid, Heflin said about 1 p.m. It was not immediately known how long the repair work would take.

About 1:15 p.m., Long Beach police announced the following street closures because of the outages: Ocean Boulevard between Magnolia and Pacific avenues; and Third Street between Magnolia and Cedar avenues.

Meanwhile, police in the neighboring city of Signal Hill announced that they were monitoring the situation in case the planned outages for repair work affected their city.

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