At least one person died and four were rushed to hospital after a multi-story parking garage in New York City collapsed on Tuesday, emergency responders said.
Aerial video footage circulating on social media showed cars piled on top of one another in a jumble of cracked concrete in the financial district of Lower Manhattan.
The building on Ann Street "pancaked, collapsed, all the way to the cellar floor," the acting head of New York's buildings department, Kazimir Vilenchik, told a press conference at the scene.
Its exterior remained standing, but officials said they feared further collapse.
The fire department's chief of operations John Esposito said they had ordered all their initial responders out of the building -- but that a robotics unit had been able to deploy a robot dog and fly drones inside to conduct searches.
He said they believed there had been six workers in the building when it collapsed.
"Four of them have been transported to the hospital in stable condition. We have one patient that has died," he told the news conference.
The sixth person refused medical treatment, he said.
Esposito said the fire department believed everyone had been accounted for.
Officials were calling for New Yorkers to avoid the area.