Footage appears to show helicopter's erratic flight path before Manhattan crash

Video from New York has reportedly captured a helicopter's terrifying flight path before it crash-landed onto the roof of a Manhattan building.

The helicopter's pilot was killed in the crash, which happened in the early hours of Tuesday morning (NZ time).

New York-based twitter user Cooper Lawrence posted video she says is of the helicopter before it crashed.

"Helicopter crashed into a building in Midtown Manhattan at 51st and 7th. Here is footage of the helicopter flying erratically before the crash."

Ms Lawrence said the footage was shot by a friend of hers, Wendy Slater.

The footage shows the helicopter flying through the air, diving and quickly losing altitude before rising again.

It then disappears into the clouds, headed away from the camera. It has not yet been confirmed the helicopter in the footage is the same one that crashed.

New York Governor Andrew Cuomo told media after the crash there is no reason to believe the crash is suspicious or could have been related to terrorism.

"The only indication was a helicopter had to do an emergency or a hard landing or crashed on to the rooftop of the building, causing a fire."

An office building in the area was evacuated and people from inside the building told media it was a scary situation.

"It was a little nerve-wracking in the stairwell because nobody knew what was going on but we did feel the tremors so that's what made it a little more surreal."

Newshub.