NEW YORK -- A crane collapsed at a New York City construction site Wednesday, injuring seven workers, authorities said.

Officials said the mobile crane unit collapsed shortly before 2:30 p.m. The construction site is behind the famed Pepsi-Cola sign in Long Island City, Queens.

Three construction workers were trapped under the crane and had to be extricated, an FDNY deputy chief on the scene said. The most seriously injured suffered broken bones.

'Everybody started running'
Carpenter Preston White said he was standing on scaffolding about 20 feet from the ground with some colleagues when the cable on the crane snapped while moving a stack of wood.

"You could hear the cable snap, and it recoiled back toward the crane," said White. "Everybody started running out of that way because that was all that was coming, the cable. And you heard a snap, and the next thing you know, the crane just buckled and it came crashing down."

"You could hear people screaming," he said. "You could hear people calling out, trying to find people. I was surprised I was still on the deck."

A 25-story residential building is being built on the site by developer TF Cornerstone.

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Matthew Knell, who lives across from the construction site, said he "heard a big bang."

Randall Todd said he was walking his dogs nearby when he heard the sound of what he described as breaking metal.

He looked over and saw "the top horizontal arm of the crane dropping, but it folded on itself, accordion-style, including the vertical tower, which seemed to snap in half."

The cause of the collapse was not immediately clear.

In a statement, TF Cornerstone said: "Site safety is always our first priority as it relates to construction, and we are cooperating fully with all relevant authorities to try and determine what caused this occurrence."

The work at the site was being carried out by subcontractor Cross Country Construction. The crane had been leased to Cross Country Construction by New York Crane.

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