Three blasts in an underground electrical vault at Devonshire Street and Independence Avenue lifted a card-table sized square of pavement Thursday morning, knocking out power to about 2,300 customers in Chatsworth.
Some traffic lights were out, too.
"There were three blasts. The first one shook the whole building," said Dr. James A. Pasternak, whose second-floor dental office is across the street. He was able to take a cell phone photograph of smoke swirling from around the edges of the foot-thick piece of pavement.
A firetruck from Station 107 was quickly on the scene of the 8 a.m. explosion. Firefighters cordoned off the street with yellow tape. Police manned the roadblock.
Workers from the Department of Water and Power (DWP) began to arrive at about 9 a.m. They examined the damage and began to isolate and test electrical circuits before descending into the vault for repairs. There was no immediate estimate from the DWP as to when power would be restored.
There were no injuries.