Update, 10:35 p.m. A squirrel that scampered into a substation in El Cerrito caused the outage that deprived much of the East Bay of power for two and a half hours, according to PG&E.

J.D. Guidi, a PG&E spokesman, said the animal — which died — had impacted the equipment that triggered a massive power failure at 8:03 p.m., causing 45,000 people to be without electricity. Power was restored around 10:30 p.m. The affected cities included Berkeley, Oakland, Albany, El Cerrito, Kensington, Richmond and San Pablo.

Update: 10:25 p.m. Still no official word from PG&E on the cause of the power outage but people began reporting via Twitter around 10 p.m. that power was returning to various parts of Berkeley.

Original story: An estimated 45,000 people in Berkeley and the surrounding East Bay area experienced power outages Monday night, according to PG&E spokesman J.D. Guidi at around 9:45 p.m.

Affected areas included parts of downtown and North Berkeley, South Berkeley, West Berkeley and the Elmwood, as well as areas of Oakland, Richmond, Albany, El Cerrito and San Pablo.

Starting at around 10 p.m., reports began coming in via Twitter that power had been restored to much of the area.

According to the PG&E outage map, PG&E estimated that power would be restored by 10:45 p.m.

First reports began coming in to Berkeleyside via Twitter around 8 p.m.

At 8:11 p.m. Sean Rouse tweeted that power was out in South Berkeley, and included information from PG&E’s outage map:

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This was quickly followed by tweets about outages downtown, in North Berkeley and in the Elmwood.

At 8:16 p.m. Lisa V-S followed with a report from North Berkeley:

TheGina tweeted at 8:17 p.m. that the Gourmet Ghetto was affected:

At 8:20 p.m., BART said on its Twitter feed that trains would run through downtown Berkeley without stopping because of the outage. BART wrote it would be bringing generators online “as quickly as possible.”

AC Transit was providing bus service from the Ashby and North Berkeley BART stations to downtown, according to BART on Twitter.

Berkeley police sent out a Nixle alert at 8:38 p.m. saying there was a “large power outage affecting the city of Berkeley.” The alert continues: “PG&E is currently investigating the cause. The lights are out at several intersections. When driving, intersections with complete power outages should be considered the same as a four-way stop sign. Please stop and proceed with caution.”

The commercial district in the Elmwood was without power at around 9 p.m.

According to local resident Ted Friedman, an employee of the Rasputin Music record store on Telegraph Avenue was temporarily trapped in an elevator due to the outage. The Berkeley Fire Department responded to the scene to rescue the employee.

Just before 9 p.m., @banx tweeted that it wasn’t all gloomy: “In lighter news, there are so many people out taking walks and playing music on their porches,” he wrote.

The last major power outage in Berkeley happened in January when 38,000 PG&E customers — including 29,000 in Berkeley, were left without power due to an equipment problem that arose at a substation in El Cerrito during planned maintenance.

Berkeleyside updated this story as we gathered more information. Read past power outage coverage on Berkeleyside.

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