The pilot of a helicopter died after it crash landed on top of a skyscraper in Manhattan, fire officials say.
New York Governor Andrew Cuomo said the 54-storey office building on Seventh Avenue shook from the impact.
Governor Cuomo said the crash sparked a rooftop fire, which was being brought under control. Some were evacuated from the tower, but none were hurt.
He said New Yorkers have “a level of PTSD from 9/11” when they hear news of an aircraft crash in Manhattan.
The incident happened at around 14:00 (19:00 GMT) on a rainy and foggy Monday.
Governor Cuomo said preliminary reports indicate the helicopter made a forced landing, but there was no indication of foul play.
He told reporters at the scene: “There was a helicopter that made a forced landing, emergency landing, or landed on the roof of the building for one reason or another.
“There was a fire that happened when the helicopter hit the roof. People that were in the building said that they felt the building shake.”
He added: “If you’re a New Yorker you have a level of PTSD from 9/11.
“As soon as you hear an aircraft hit a building my mind goes where every New Yorker’s mind goes.”
Witnesses outside the building told reporters that no debris was visible on the pavement or in roadways below the scene of the incident.
Fire officials said on social media they were working to respond to “fuel leaking from the helicopter”.
Nancy Berman, who works nearby, told BBC News: “I was sat at a table in my office and we all felt furniture move.
“It was like a little shake. But we didn’t think anything of it.
“An announcement on the office loudspeaker told us there had been a crash and the other building were evacuating.”
She said employees in her office chose to stay put.
President Donald Trump has been briefed on the incident, White House Press Officer Hogan Gidley confirmed.
According to the New York Post, there is no helicopter landing pad on the roof of the building, 787 Seventh Avenue.
Zach Escalante, a computer programmer who works on the third floor, told the newspaper: “We felt the building move.”