A contractor in charge of raising the crane that toppled in midtown Manhattan and killed seven people has been indicted on homicide charges, the district attorney said Monday.

William Rapetti, the head of Rapetti Rigging Services Inc., and his company were indicted in the March 15 collapse, Manhattan District Attorney Robert Morgenthau said.

The prosecutor wouldn't elaborate on the charges and planned a news conference later Monday.

Six construction workers and a Florida tourist in town for St. Patrick's Day weekend died when the 19-story tower crane toppled like a tree from a luxury apartment tower under construction. The accident destroyed a four-story townhouse and damaged many other buildings.

Rapetti's attorney, Arthur Aidala, said in an e-mail that Rapetti, a crane rigger and operator, surrendered to prosecutors Monday. He said Rapetti is innocent.

"William Rapetti and Rapetti Rigging have a long and distinguished record of excellence, safety and public service spanning decades," Aidala said. "William Rapetti is determined to help clear his name and demonstrate that he and his company operated and supervised the site in a manner beyond reproach."

Rapetti's company in Massapequa Park was one of three contractors fined over $300,000 by the Occupational Safety and Health Administration for safety violations stemming from the collapse.

The agency said Rapetti had failed to comply with the crane manufacturer's specifications when erecting and raising the steel tower, and didn't provide enough safety protection to keep workers from falling.

Rapetti was also cited for improperly using slings to stabilize the crane.

The crane toppled while workers were trying to lengthen the crane along the tower. Investigators have said that a steel brace attaching the crane to the tower fell and dislodged the braces below it.

The accident was one of a spate of fatal construction accidents in the city, including a second crane collapse in May that killed two workers. The city building commissioner resigned two months after the collapse amid revelations that the 43-story tower under construction was mistakenly approved.

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