Investigators are looking into the cause of this morning's collapse of a mobile crane in Hell's Kitchen near the the exit from the Lincoln Tunnel.

Fire officials say there were no injuries when the crane fell around 8:45 a.m. at 438 West 38th Street, between 9th and 10th Avenues.

The mobile crane, which was mounted on the back of a truck in a vacant lot, tipped over as it tried to lift an air conditioning unit off of another truck to the top of a nearby building.

As the crane fell over onto the street, passersby said they hear a large bang.

"It sounded like something just fell outside our window. I don't know, I mean, I thought it was in the kitchen, but it was just this huge, loud thump," said one resident.

"I thought maybe someone fell. Like, I didn't think there would be a crane," said another.

The Buildings Department is still investigating the incident.