A charter Helicopter crashed in New York City on March 11 with one survivor and 5 other trapped in the sinking wreckage.

Two of the passengers were pronounced dead in the initial hours after the crash and three others died later at a hospital, according to The Washington Post.

The Federal Aviation Administration and the National Transportation Safety Board are still investigating the cause of the crash.

“It’s a great tragedy that we had occur here on an otherwise quiet Sunday evening,” New York City Fire Department Commissioner Daniel A. Nigro said at a Sunday-night news conference.

The Washington Post informed that a helicopter carrying six passengers sent out a mayday shortly after takeoff. Videos captured by witnesses show the craft descending quickly, capsizing and tilting to one side, with its rotor blades still spinning in the frigid water.

“The pilot managed to free himself and call out for help from a flotation device,” witnesses said to the Washington Post.

The Washington Post said the other five passengers, who were less experienced, were harnessed into their seats and could not escape the crash.

“Rescue teams worked in below -40-degree temperatures and 50-foot-deep water to remove the passengers from the helicopter,” Nigro said to Washington Post. “It took a while for the divers to get these people out.”

The names of the deceased are Trevor Cadigan, Brian McDaniel, Daniel Thompson, Tristan Hill and Carla Vallejos Blanco.