The controlled demolition of a California power plant sent shrapnel flying into a crowd of 1,000 spectators, injuring five people, including one man whose leg was severed.

A crowd gathered just before 6 a.m. Sunday morning in Bakersfield, Calif., in a so-called "safe zone," 1,000 feet away from where the two 140-foot-tall steel boilers were rigged with explosives.

Seconds after the charges were detonated and the building came crashing into the ground, spectators began screaming as shrapnel including chunks of steel whizzed into the crowd.

"It felt like a piece of metal hit me," spectator Fred Garten, 49, told KABC-TV. "It felt like getting hit by a baseball bat right below the knee."

Cleveland Wrecking Co. of Covina, Calif., the contractor hired to conduct the demolition issued a statement apologizing for the injuries.

"This was a terrible accident, and our hearts go out to the individuals who were injured," the statement read. "We will be conducting a full investigation and will cooperate with the authorities."

One victim, a 44-year-old man, sustained a serious injury to his leg and will likely need to have it amputated, officials said.

The plant, owned by Pacific Gas and Electric was decommissioned in 1986 and had been idle ever since.

The power company said it was working with "all investigative agencies and third-part contractors" to determine what went wrong.