NEW YORK -- The New York City medical examiner said a second person has died as a result of the Manhattan crane collapse.

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The medical examiner's spokeswoman, Ellen Borakove, said the victim was a 27-year-old man, Ramadan Kurtas.

The accident also killed the crane's operator, identified as 30-year-old Donald Leo of Staten Island.

The construction crane collapsed Friday morning on New York's Upper East Side, smashing into a nearby 23-story apartment building and then crashing onto the street below.

The crane hit an apartment building, shredding a corner of the penthouse, before crashing onto the street below.

New York Mayor Michael Bloomberg said seven buildings were evacuated as a precaution.

He said one of the casualties was in the cab of the crane and a second was on the street.

He said he didn't know about the third person, and he didn't say who was killed.

It was the city's second deadly crane accident in 2½ months. The first crane accident killed seven people about two miles south, near the United Nations. The collapse demolished a four-story townhouse. Bloomberg called the latest collapse "unacceptable and intolerable" and said the city will investigate.

"We do not know at the moment what happened or why," Bloomberg said, adding that the crane was inspected and "fully in compliance with building regulations."

A witness across the street said the collapse sounded "like a thunder clap. Then, an earthquake."

He said the entire cab came off the crane.

Another witness said there was "a big boom" and suddenly "everybody was yelling and running and calling 911."

One man heard the "loud bangs" from down the street.

"It sounded catastrophic, and that's from two blocks away," he said.

A WNBC-TV helicopter in New York showed a large portion of the crane tumbled onto the building.

Firefighters were combing through the wreckage, searching for survivors.

One body was placed on a gurney and covered in a white sheet. A construction worker knelt over the gurney, gently stroking the sheet.

The foreman himself escaped injury because he'd gone to grab a sandwich. He then ran back to the construction site to take a roll call of his 40 workers. He said everyone was crying.

"These are some hardened men, but they were crying," he said.

Officials said fire crews pulled other people out of the wreckage. Their conditions were not immediately known.

Last month, the city's buildings commissioner resigned, under fire over a rising number of fatal construction accidents.