The official post-mortem report from the coroner's office has yet to be released, but the death certificate indicated Mr Brown died of a gunshot to the skull.

"It was a 'kill' shot to the back of the head," said Mr Crump, citing the private post-mortem carried out by Brent Hall, a former medical examiner in Boone, North Carolina.

"It went into the base of the neck, bottom of the skull and got lost in his brain. That was the cause of death."

At a news conference, some of Mr Brown's relatives were joined by mothers who sons were killed in police incidents.

They condemned his death.

"This is what they do in the black and brown communities. They come to us, they brutalise, they terrorise, they kill," said Gwen Carr, the mother of Eric Garner who died after he was held in a chokehold by an officer.

"It's horrible what they do to us. And it has to stop. It has to stop," Ms Carr added.

Mr Brown's death led to several nights of protests in Elizabeth City.

And it came one day after former Minneapolis police officer Derek Chauvin was convicted of murdering George Floyd in a trial that put a spotlight on police violence against black people. 

Reference: Sky News: