(CNN) The man who opened fire on a crowded bar district in Dayton, Ohio, had cocaine in his system, the county coroner said Thursday.

Cocaine, anti-anxiety medication and alcohol were found in Connor Betts' blood during the autopsy, Montgomery County Coroner Kent Harshbarger said at a press conference.

Preliminary autopsy results also found that two of the victims were also struck by police bullets, he said.

Armed with a .223-caliber high-capacity rifle, Betts opened fire on August 4 in the popular Oregon district, killing nine people, including his sister, and wounding 17 others. He was killed by patrol officers 30 seconds after he opened fire.

"A pipe device was found in his pocket with an attached clear plastic baggie that has been determined to contain cocaine," Harshbarger said. "And the assailant's cavity blood sample was found to contain cocaine, alprazolam and ethanol."

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