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 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 pilot was the only person aboard the Agusta A109E helicopter, said the Federal Aviation Administration (FAA).
The incident happened at around 14:00 (19:00 GMT) on a rainy and foggy Monday.
Governor Cuomo said preliminary reports indicate 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, right, from 9/11. And I remember that morning all too well.
"So as soon as you hear an aircraft hit a building, I think my mind goes where every New Yorker's mind goes."
She said employees in her office chose to stay put.
According to the New York Post, there is no helicopter landing pad on the roof of the tower at 787 Seventh Avenue.
The scene, which is close to Times Square, led employees to clear out of buildings as emergency response vehicle sirens wailed in the streets.
The National Transportation Safety Board will investigate the incident.
The White House said President Donald Trump had been briefed on the incident.
Source: BBC