Mansur Ball-Bey, the black 18-year-old killed by white St. Louis officers earlier this week, died from a single gunshot in the back, according to an autopsy report.

The autopsy's findings were first reported by the St. Louis Post-Dispatch. There were two officers involved in the shooting; one fired three times and another fired just once, police told the paper.

The investigation of the shooting is ongoing.

However, St. Louis Police Chief Sam Dotson tells the Post-Dispatch that the location of the fatal wound does not confirm or contradict the officers' account that Ball-Bey pointed a gun at them before he was shot.

" 'Just because he was shot in the back doesn't mean he was running away,' Dotson said. 'It could be, and I'm not saying that it doesn't mean that. I just don't know yet.' "

As St. Louis Public Radio reports, police officers were attempting to serve a warrant Wednesday when "two young black males armed with guns" ran out a back door. Officers ordered the men to drop the gun before firing.

As we reported, Ball-Bey's death ignited a fresh round of clashesbetween protesters and law enforcement in St. Louis. Protesters threw bricks and other objects at police before officers in riot gear arrived on the scene.

Dotson defended police tactics Wednesday night when they made nine arrests and fired tear gas at protesters.

Tensions in the St. Louis area remain high. This latest incident comes less than two weeks after mourners marked the anniversary of the death of Michael Brown, who was killed by a white police officer last year in nearby Ferguson, Mo.

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