One of the deceased is reportedly a billionaire coal-mining tycoon from West Virginia. The others have not been identified.
Police and emergency teams responded to calls regarding a crash landing on top of a 54-story office building in midtown Manhattan.
Thick plumes of smoke were seen in midtown Manhattan Monday afternoon after a helicopter made a hard landing on top of a 54-story office building.
There were reports of at least one fatality.
The pilot, named as William "Bill" Denio, was hurt in the crash but is now in a stable condition.
Helicopter went down during routine training exercise in southern California.
Pilot desperately tried to save pair from wreckage after helicopter plunged into ocean.
"The pilot freed himself. The other five did not," FDNY Commissioner Daniel Nigro said.
It was unclear how many people were on board.
The helicopter, lost on an earthquake relief mission, was found high on a mountainside in Nepal with three bodies recovered and five feared dead.
Reports from the field indicated the helicopter's crew was overheard talking about fuel problems.