Michael Brown, the unarmed black teenager killed by Officer Darren Wilson in Ferguson, Missouri, on August 9, was shot at least six times, including twice in the head, medical examiner Michael Baden has said.

Dr. Michael Baden was hired to perform a second, independent autopsy by the family of Michael Brown, 18.

They have called for the arrest of the officer who killed Michael Brown.

Michael Brown’s death has sparked days of unrest and clashes between protesters and police in the St. Louis suburb.

Darren Wilson has been suspended with pay since the shooting, and Michael Brown’s family have called for his arrest and prosecution.

Michael Brown was shot at least six times, including twice in the head

As the unrest, marked by a crackdown by armed police wielding tear gas and rubber bullets, has continued, on Sunday Missouri Governor Jay Nixon ordered the National Guard to the town to “help restore peace and order”.

Dr. Michael Baden, a veteran of the New York City medical examiner’s office and nationally prominent forensic pathologist, said in a news conference on Monday that his preliminary findings could answer the family’s basic questions, including how many times he was shot and if he suffered.

He and forensic pathologist Shaun Parcells said Michael Brown was shot at least six times, twice in the head. They believed at least two bullets left re-entry wounds. One bullet entered the top of his head. Michael Brown was 6ft 4in tall.

Shaun Parcells said a wound to Michael Brown’s right arm may have been sustained as he had his hands up, “but we don’t know”. He said the wound was consistent either with having his back to the officer or facing the officer with his hands above his head or in a defensive position.

Both men said more information was needed, including x-rays from the initial autopsy, the medical evaluation of Darren Wilson and the clothes Michael Brown was wearing at his time of death.

Dr. Michael Baden said there were no signs of a struggle, as abrasions around the teenager’s face were likely from falling to the pavement after being shot.

He also believed Darren Wilson did not shoot him at close range as there was no gunpowder residue on his body, suggesting the officer was at least 2ft away.

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