Police in Minnesota have been condemned by the family of a black man who was shot dead by officers during a traffic stop.

The man, named by relatives as Philando Castile, died minutes after arriving at hospital following the incident in the Falcon Heights suburb of the state capital, St Paul.

His cousin Antonio Johnson said Mr Castile was "a black individual driving in Falcon Heights who was immediately criminally profiled".

Family members at Hennepin County Medical Centre said Mr Castile was a 32-year-old cafeteria supervisor at a Montessori school.

His uncle Clarence Castile said the victim had worked in the JJ Hill school cafe for 12 to 15 years and was a "good kid".

Reports earlier said Mr Castile was shot while inside a car with a woman and a child.

A video posted on Facebook appeared to show a woman sitting in a car with a man whose shirt looked to be soaked in blood, saying an officer had shot her boyfriend.

Dozens of protesters gathered at the scene chanting: "We will stand our ground. We will not move," as officers attempted to clear the area.

St Anthony Police Department spokesman Jon Mangseth said the officer involved is on paid administrative leave pending an investigation.

The shooting came as the Justice Department launched a civil rights investigation into the video-recorded killing of a black man who was shot as he scuffled with two white police officers in Baton Rouge, Louisiana, which has sparked more protests.