FERGUSON, Mo. -- An unarmed 18-year-old whose fatal shooting by police has sparked rancorous protests in suburban St. Louis suffered a bullet wound to his right arm that may indicate his hands were up or his back was turned, but "we don't know," a pathologist hired by his family said Monday.
An independent autopsy determined that Michael Brown was shot at least six times, including twice in the head, the family's lawyers and hired pathologists said. Witnesses said Brown's hands were above his head when he was repeatedly shot by an officer on Aug. 9 in Ferguson, where the governor called in the National Guard early Monday after police again used tear gas to quell protesters.
Forensic pathologist Shawn Parcells, who assisted former New York City chief medical examiner Dr. Michael Baden during the private autopsy, said a bullet grazed Brown's right arm. He said the wound indicates Brown may have had his back to the shooter, or he could have been facing the shooter with his hands above his head or in a defensive position across his chest or face.
"We don't know," Parcells said. "We still have to look at the other (elements) of this investigation before we start piecing things together."
Brown's death has heightened racial tensions between the predominantly black community and Ferguson's mostly white police department. Another protest quickly deteriorated Sunday night as marchers pushed toward one end of a street, and authorities -- who said they were responding to reports of gunfire, looting, vandalism and protesters hurling Molotov cocktails -- pushed them back with tear gas.
It was unclear when National Guard troops would arrive, but Gov. Jay Nixon said they would be under the direction of the Missouri State Highway Patrol, which is overseeing security during protests.
"These violent acts are a disservice to the family of Michael Brown and his memory, and to the people of this community who yearn for justice to be served and to feel safe in their own homes," Nixon said in a statement.
Nixon also lifted the neighborhood's midnight-to-5 a.m. curfew Monday, two days after it went into effect when he declared a state of emergency.
But police were telling protesters Monday afternoon that they couldn't assemble in a single spot, saying they had to keep moving per an order from the Highway Patrol. Two men were arrested for disorderly conduct and failure to disperse, according to a police commander.
A grand jury could begin hearing evidence Wednesday to determine whether the officer, Darren Wilson, should be charged in Brown's death, said Ed Magee, spokesman for St. Louis County's prosecuting attorney.
The St. Louis County medical examiner's autopsy found that Brown was shot six to eight times in the head and chest, office administrator Suzanne McCune said Monday. But she declined further comment, saying the full findings weren't expected for about two weeks.
Family attorney Benjamin Crump said Brown's parents wanted the additional autopsy because they feared results of the county's examination could be biased. Crump declined to release copies of the report.
"They could not trust what was going to be put in the reports about the tragic execution of their child," he said during Monday's news conference with Parcells and Baden, who has testified in several high-profile cases, including the O.J. Simpson murder trial.
The second autopsy, Crump said, "verifies that the witness accounts were true: that he was shot multiple times."
Baden said one of the bullets entered the top of Brown's skull, suggesting his head was bent forward when he suffered that fatal injury. The hired pathologists said Brown, who also was shot four times in the right arm, could have survived the other bullet wounds.
Baden also said there was no gun-power residue on Brown's body, indicating he was not shot at close range. However, Baden said he did not have access to Brown's clothing, and that it was possible the residue could be on the clothing.
Crump also noted that Brown had abrasions on his face from where he fell to the ground, but there was "otherwise no evidence of a struggle."
Associated Press writers Jim Salter in St. Louis, David A. Lieb in Jefferson City, and Nigel Duara in Ferguson contributed to this report.