THE pilot of a tourist helicopter has survived, but his five passengers have died after he crashed in New York's East River where eyewitnesses saw it plunge into the water and then tip over.
The NYPD and Fire Department of New York went to East 90 Street, where witnesses saw the chopper plunge into the water.
The chopper went down near Gracie Mansion at about 7.15pm local time, a high-ranking source said, according to The New York Post.
A spokesman for NYC Mayor Bill de Blasio confirmed at least two passengers were dead.
Police divers rescued three others who were taken to hospital. They were critical, but have since died.
A Federal Aviation Administration spokeswoman says the Eurocopter AS350 went down in the waterway just north of Roosevelt Island and is "reportedly inverted in the water."
Within minutes, the helicopter disappeared beneath the waves, witness John Magers, 24, told The New York Post.
"It looked like it was completely submerged," he said.
"It couldn't have been any longer than 5 minutes."
The pilot was able to get out and climb aboard a raft, The New York Post reports. He managed to walk over to an ambulance where he received further medical treatment. The moment was captured on video and posted to Twitter.
Magers said he saw police drop divers into the river.
Witness Mary Lee, 66, told The New York Post that she saw the chopper go down from her apartment window and said she "immediately thought someone was in there and not going to live - it's cold water, it was sinking really fast.
"By the time we got out here, we couldn't see it. It was under water."
Video posted on Twitter shows a red helicopter land hard in the water and then tip over as its rotors slap at the water.
A witness told NY1, "We heard it hit the water, and then automatically, it drowned."
Her friend added, "It landed to the side, and then it flipped over, and then for about a minute and a half, no one came out of the water, so all of us immediately called 911. And then we saw one guy climb onto the raft."
Brianna Jesme, 22, who witnessed the afternoon crash, told the New York Daily News: "It sort of landed sideways and then it flipped over. There was a good solid minute that no one came out of the helicopter."
She added, "We didn't know if it was supposed to be happening. Once it went down we realised that it wasn't supposed to happen."
There are only two Eurocopter AS350's registered with the FAA in the tri-state area - both to the New Jersey parent company of tour operator Fly Liberty Charters, FAA records show.
Fly Liberty could not immediately be reached for comment.
The FAA and the National Transportation Safety Board are investigating.
A cause for the crash has not been identified yet.