Investigators probe whether faulty repairs caused crane collapse

NEW YORK (CNN) -- Investigators probing last week's fatal collapse of a construction crane are looking into whether a part of the machine had been returned to service without proper repairs, the Manhattan district attorney's office said Monday.

Those investigators are examining whether the turntable that connected the operator's cab and the crane's boom to the tower was damaged during a 2007 project and never properly repaired, said Barbara Thompson, spokeswoman for the prosecutor's office.

Investigators suspect the damaged part caused the cab and boom to crash into a 23-story apartment building on the Upper East Side on Friday, killing two construction workers and forcing hundreds from their homes due to damage to the building.

The crane's owner, New York Crane and Equipment Corporation, did not return phone calls seeking comment.

The crane was being used in the construction an apartment building in the heavily residential area.

Its fall heavily damaged the 23-story building across the street, gouging chunks out of a rooftop penthouse and balconies down the side. See photos of the collapse »

New York Mayor Michael Bloomberg has promised an investigation after two similar crane collapses in the past two months.

"There are too many accidents, and we're going to see if we can do more to make sure everything is safe," he said Sunday.

The collapse occurred a day after a building inspector rescinded a partial stop-work order that had been issued April 24.

The order was issued after an inspection found employees had been working without a permit and operating a crane in an "unsafe manner," according to the city's Building Department.

According to a written statement from the New York Buildings Commission, a total of 22 complaints were made about the construction site, six of which were related to the tower crane, though no violations were issued regarding the crane.

CNN's Ekin Middleton, Amy Sahba and Laura Batchelor contributed to this report.

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