The unarmed black teenager killed by a police officer in Ferguson, Missouri, on 9 August was shot at least six times, according to a medical examiner’s report.

The family of 18-year-old Michael Brown hired Dr Michael Baden to perform a second autopsy on his body because they did not trust St Louis County police officials to conduct a thorough investigation into his death.

Working in co-operation with forensic pathologist Shaun Parcells, Baden found that Brown was shot at least six times, including twice to the head. They also found that there were no signs of a struggle, and Brown was not shot at close range as there was no gunpowder residue on his body.

Both men have called for access to the x-rays from the original autopsy as well as Brown’s clothes to help determined the exact timeline of events.

Brown was shot and killed by police officer Darren Wilson, who has been suspended with pay since the incident. The Brown family has called for his arrest and prosecution.

The boy’s death sparked a week of protests in the poor majority black Ferguson suburb of St. Luois and police have reacted by imposing military might, using rubber bullets and tear gas to disperse the crowds.