ST. LOUIS >> Michael Brown’s official autopsy indicates he was shot in the hand at close range during a struggle, but a medical examiner not involved in the investigation says there’s no way to conclude whether the injury meant the unarmed 18-year-old was trying to grab the gun of the officer who killed him.

The St. Louis County medical examiner’s autopsy report, obtained by the St. Louis Post-Dispatch, doesn’t explain why Brown was killed after the apparent scuffle at Officer Darren Wilson’s police vehicle spilled onto a Ferguson street or confirm whether he was confronting Wilson or trying to surrender when he was fatally shot — both scenarios offered by various witnesses to the Aug. 9 shooting.

The shooting of Brown, who was black, by Wilson, who is white, spurred unrest and weeks of protests in Ferguson, some of which turned violent. A grand jury is expected to decide by mid-November whether Wilson will face criminal charges, and the Justice Department is investigating for possible civil rights violations.

The autopsy showed Brown suffered six bullet entrance wounds and listed “gunshot wounds to the head and chest” as the cause of death. A toxicology report with the autopsy also showed Brown had marijuana in his system.

Dwain Fuller, a Dallas-area forensic toxicologist, told The Associated Press the report indicated “recent use” that likely meant Brown still was feeling the effects of the drug, but “as far as that making him violent, one can’t really say.”

Both the Post-Dispatch, which published a story Wednesday on the county autopsy report, and The New York Times, which ran a story last week about the officer’s account of the shooting, cited unnamed sources saying Wilson told investigators he and Brown struggled over the officer’s gun.

The autopsy said a microscopic exam showed that foreign matter found on tissue from Brown’s injured thumb was “consistent with products that are discharged from the barrel of a firearm.”

St. Louis city medical examiner Michael Graham, who was not involved in the autopsy, said that and other evidence indicates the shot to the hand probably occurred inside Wilson’s SUV. Graham, in an interview with the AP, said it’s impossible to conclude whether the close-range injury meant Brown was trying to grab the officer’s gun, as Wilson has alleged.

Judy Melinek, a forensic pathologist from San Francisco, said combined with other evidence, the autopsy indicates there was a struggle for Wilson’s gun inside the officer’s SUV.

“You don’t just look at one piece of evidence,” Melinek told the AP. “You have a witness statement, the officer, saying that Michael Brown is reaching for the gun and it goes off and hits (Brown’s) hand. The physical findings (in the autopsy) are consistent with the officer’s statement.”

Brown family attorney Benjamin Crump said the shots fired outside the police vehicle are what really matter.

“After there was no more threat, and (Brown) was running away, why did Officer Darren Wilson keep shooting?” Crump asked in an interview with the AP. “That’s what this is about. When Michael Brown put his hands up in the air, why does the officer keep shooting?”

The findings were similar to those of an autopsy commissioned by Brown’s family and released Aug. 18, said Michael Baden, the former New York City chief medical examiner who performed the independent exam.

Some of the bullet wounds indicated Brown and Wilson were facing each other on the street after moving away from Wilson’s vehicle. But forensic pathologist Shawn Parcells, who assisted Baden, told the AP there is no forensic evidence to verify whether Brown was surrendering or moving aggressively toward Wilson.

“He could have been charging the officer. He could have been walking toward the officer. He could have been standing still. He could have been stumbling,” Parcells said. “I don’t know if we’ll ever know.”

Baden agreed.

“The questions are going to go on far beyond the autopsy,” he told the AP.

Results of a third autopsy, performed by the Justice Department, have not been released.

The county autopsy also offered the first public glimpse of the St. Louis County police investigation, citing a detective’s account of events leading up to the shooting.

The report said Brown “became belligerent” when Wilson told Brown and his friend, Dorian Johnson, to stop walking in the middle of the street. The report said that when Wilson tried to get out of his vehicle, Brown pushed the door shut, leading to the struggle inside the SUV.

Brown got out of the SUV and, with Wilson giving chase, turned around and ran at the officer, the report said. Wilson “had his service weapon drawn, as the deceased began to run towards him, he discharged his service weapon several times,” the report said.

It wasn’t clear if the report was based strictly on an interview with Wilson. St. Louis County Police spokesman Brian Schellman declined comment.

Johnson has said in media interviews that Wilson, not Brown, was the aggressor. He said the officer used profanity in telling him and Brown to get to the sidewalk and nearly struck them when he backed up the SUV. He said Wilson grabbed Brown and tried to pull him into the vehicle, prompting the confrontation.

Johnson also claimed Wilson shot Brown while he had his hands up in surrender.