A crane has collapsed in New York City's Lower Manhattan, killing at least one person and injuring three others, US authorities say.

Friday morning's incident also caused a gas leak, Mayor Bill de Blasio said, forcing the authorities to shut off supply in buildings around the Tribeca neighbourhood.

The crane's boom landed across an intersection and stretched much of a block after the accident around 8.25am, about 10 blocks north of the World Trade Center.

De Blasio originally said the victim was sitting in a parked car when the crane collapsed, but police later said he was on the footpath.

The large crane smashed the roofs of nearby buildings with debris littering the street.

De Blasio said the crane was being lowered as a precaution because of wind when the accident happened.

The crew had been directing people away from the area as the crane was being moved.

Firemen survey the damage of a fallen crane in Worth Street, Lower Manhattan, New York City [Jason Szenes/EPA]

"It was right outside my window," Robert Harold, a witness who works at the Legal Aid Society, told the Associated Press news agency.

"It was a crashing sound. You could feel the vibration in the building."

Harold said at least one person was trapped in a car, and he saw onlookers trying to get the person out.

He said he also saw a person lying motionless on the street.

The crane bore the name of Bay Crane company.

An employee at the company, who said he was a manager but did not give his name, told AP that an investigation was under way. He declined further comment.

Members of the New York City Fire Department survey the damage of a fallen crane on 40 Worth Street [Jason Szenes/EPA]

Source: AP