An abandoned power plant collapsed during a demolition project Monday, killing a worker and seriously injuring two others.

One worker escaped with the help of co-workers and was taken to a hospital with a life-threatening leg injury, Fire Department spokeswoman Mindy Talmadge said. A second was trapped for more than half an hour before being taken to a hospital with "crushing leg injuries."

The body of the third worker remained under metal rubble for hours after the collapse, Talmadge said, while inspectors tried to determine the safest way to reach it.

"It was a steel beam structure. It was four to five stories high, and on each of the levels was big, heavy boiler equipment," Talmadge said. "It was a structure that didn't have any concrete around it or anything."

Marti Paschal, a spokeswoman for San Francisco General Hospital, said that one of the survivors was admitted in serious condition and that the other was stable.

The power plant had recently been decommissioned, said Pacific Gas and Electric Co. spokesman David Eisenhauer.

"Our first concern, our main concern, is with the welfare of the folks out there," Eisenhauer said.

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