NEW YORK — The fatal New York City helicopter crash that killed everyone on board except the pilot may have been caused by a passenger’s piece of luggage, the pilot told investigators.

The pilot said one of the passenger’s bags may have inadvertently hit the emergency fuel shutoff button, leading to the crash that killed five passengers, a senior law enforcement official said.

The National Transportation Safety Board will try to determine the cause of the Sunday evening crash, the Federal Aviation Administration said. The NTSB tweeted that an investigation team of 14 people would arrive Monday morning.

The passengers were on a Liberty Helicopters chopper that had been chartered for a private photo shoot, authorities said.

“One of the most difficult parts of the rescue were that five people were tightly harnessed,” Fire Department of New York Commissioner Daniel Nigro said. “People had to be cut out.”

The pilot was able to free himself and was rescued, Daniel Nigro said.

In an audio recording of a mayday call to LaGuardia Airport, the pilot can be heard saying that the helicopter was experiencing engine failure.

Company had 3 crashes in 11 years

Liberty Helicopters describes itself on its website as “the largest and most experienced helicopter sightseeing and charter service in New York City.”

The company has “a fleet of 10 state-of-the-art Airbus helicopters (formerly American Eurocopter),” according to the website. “We have been in business and flying safely for over 30 years,” the website says.

This is the company’s third crash in 11 years, according to CNN affiliate WABC-TV. In August 2009, nine people were killed after a helicopter and a small, private plane crashed into each other over the Hudson River. Investigators said the helicopter was flying too high.

Two years before that, in July 2007, a Liberty sightseeing chopper carrying eight people dropped into the Hudson river. An off-duty paramedic on board helped everyone escape, WABC reports.

The Federal Aviation Administration said on Twitter that the helicopter went down in the river near Roosevelt Island at 7 p.m. ET. The FAA identified it as a Eurocopter AS350.

The helicopter was upside down and submerged when emergency responders reached it, authorities said.

Police said the chopper was in the water around 23rd Street and called for a barge with a crane to pull it out.

Crash investigation

The NTSB will likely look at three things: the pilot’s training, experience and immediate response during the crash; what, if anything, on the helicopter caused the crash; and what environmental factors may have contributed to the crash, said Gary C. Robb, an aviation attorney based in Missouri.

Robb says the NTSB would then release a preliminary report, and a probable-cause accident report would follow detailing what happened during the crash.

John J. Magers filmed the crash as it took place and posted the video on Twitter. He said he thought something was strange when he saw the helicopter flying low before it crashed into the East River, so he started shooting video.

“I saw it coming down toward the water. Thought it was unusual, but didn’t expect it to crash,” Magers told CNN. “My thoughts are with those killed.”