Washington plane crash: Moment plane collides with military helicopter, plunges into Potomac River

Terrifying vision shows the moment a passenger plane carrying 64 people collided with a military helicopter over Washington DC.

The plane, being operated by regional airline PSA, was approaching the runway at Reagan Airport when it collided with a Black Hawk helicopter carrying three US army personnel.

Video from an observation camera at the nearby Kennedy Center shows two sets of lights consistent with aircraft appearing to join in a fireball.

The plane can be seen plunging into the Potomac River just seconds after impact.

A major search and rescue operation is underway, with officials confirming four survivors have been pulled from the river.

WATCH THE VIDEO ABOVE