NEW YORK -- Five people were killed in a helicopter crash on New York City's East River, authorities said. The aircraft -- a Eurocopter AS350 -- went down near Roosevelt Island around 7 p.m. Sunday, the Federal Aviation Administration (FAA) said in a statement.

Six people were aboard when it crashed, the Coast Guard said in a statement. One person was rescued by a tugboat and five others were "recovered by divers," it said.

The pilot freed himself from the chopper, but the others were unable to free themselves, FDNY Commissioner Daniel A. Nigro said in a news conference Sunday evening. Divers with the city's police and fire department were able to free the passengers, he added. The pilot was treated and released from a hospital.

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Three of the victims were rushed to nearby hospitals in critical condition and two were pronounced dead at the scene, Nigro said. The three who were raced to hospitals later died, the FDNY said. Authorities did not identify the names of the pilot or passengers.

Paramedics and members of the NYFD perform CPR on a victim of a helicopter that crashed into the East River in New York on Sun., March 11, 2018. Reuters

The helicopter is owned by Liberty Helicopter Tours and was hired for a private photoshoot, New York City police Commissioner James P. O'Neill said.

The National Transportation Safety Board (NTSB) said it was sending a team to investigate the crash.

Liberty was involved in at least two prior crashes: On August 8, 2009 , one of its tour choppers collided with a private plane over the Hudson River, killing nine people. The investigation determines helicopter was flying too high. And on July 7, 2007, a Liberty sightseeing helicopter carrying eight dropped 500 feet into the Hudson, but an off-duty EMT aboard helped everyone escape.

Video on social media appeared to show the latest crash -- the red chopper hitting the river:

@cnn @FoxNews just witnessed a helicopter crash into the East River .. hope everyone’s ok. Caught it all on tape! pic.twitter.com/saHOMTLR69 — JJ Magers (@JJmagers) March 11, 2018

The helicopter reported an engine failure during a the mayday call to air traffic control, according to audio posted to liveatc.net. The audio revealed that the helicopter was upside down in the water as rescue boats arrived at the scene.

Witnesses said the chopper appeared to quickly fill with water. Mary Lee, 66, told the New York Post she witnessed the crash from her apartment window.

"It's cold water. It was sinking really fast," Lee said. "By the time we got out here, we couldn't see it. It was under water."

A helicopter crashed in New York City's East River on Sun., March 11, 2018, in this picture obtained from social media. John J. Magers via Reuters

Another witness said she saw the helicopter descending rapidly before hitting the water.

"It almost looked like it was landing," Xinran Jiang, who witnessed the crash from her bedroom window, told The New York Times. "It wasn't moving fast. We were curious where it was going to land. Then the next minute, it was diving into the river."