Aftermath of another fatal US police shooting of black man streamed live on Facebook - by victim's girlfriend

A black man has been fatally shot by police in Minnesota - with his girlfriend filming the aftermath in a Facebook Live video.

Philando Castile, 34, was shot in his car on Wednesday as he reached for his driving licence after being pulled over for a broken tail light.

His girlfriend's young daughter was in the car at the time.

It comes amid widespread protests over the death of Alton Sterling, who was shot dead by police in Baton Rouge, Louisiana on Tuesday,

The deaths are likely to spark more debate about police's treatment of African-Americans, with both #FalconHeightsShooting, #BlackLivesMatter and 'American Police' among the top trends on Twitter on Thursday morning.

Castile is seen bleeding heavily in the driver's seat as a police officer points a gun through the window in the incredibly graphic footage, filmed by his girlfriend Lavish Reynolds.

She said her boyfriend had told the officer that he had a gun, which he had a licence to carry.

"He was trying to get out his ID and his wallet out of his pocket," she said.

"He let the officer know that he had a firearm and that he was reaching for his wallet and the officer just shot him in his arm."

She is later heard saying: "He's killed my boyfriend. Please don't tell me he's dead...please don't tell me officer that you've just done this to him sir."

Officers told the woman to keep her hands up as a small child is heard crying in the background.

"F***, I told him not to reach for it," a distraught man is heard screaming in the video.

Police confirmed a man was shot inside a car with a woman and child, but did not release his name or comment on the video.

Officers also confirmed that a handgun was recovered at the scene and the unnamed officer involved has been put on leave.