Man live-streams shooting to Facebook

A US man live-streamed his own brutal shooting after a gunman pelted his car with a barrage of bullets.

T.J. Williams was parked in Norfolk, Virginia with two other men listening to music using Facebook's live streaming service when they were allegedly approached by a person off camera.

Video shows the camera drop to the ground and gunfire erupt as bullets tear through the car.

The onslaught lasts for almost 20 seconds with neighbours telling police the gunman fired at least two dozen rounds, ABC13 reports.

The camera - covered in glass and debris - continues to record as a man off screen can be heard rushing over to the vehicle to comfort the occupants.

"Give me your hand. Stay relaxed. I got you. Stay relaxed," he told the men as a second bystander called an ambulance.

"They're coming. They're coming to get you."

The victims, who are all aged under 30, were transported to hospital with life threatening injuries.

The Facebook live feed continued for more than an hour as paramedics retrieved the men and police cordoned off the crime scene.

Police are investigating the shooting and the motives behind it.

No arrests have been made so far.