Evidence shows four of the nine people killed in a melee between rival biker gangs outside a Texas restaurant were struck by the same caliber of rifle fired by Waco police.

The latest trove of potential grand jury evidence obtained by The Associated Press provides the most insight yet into whether authorities were responsible for any deaths.

Extensive audio, footage and documents depict a bloody scene on May 17.

Ballistics reports show four of the dead were shot by .223-caliber rifles — the only type of weapon fired by police.

Two had wounds from only that kind of rifle; the other two were also struck by other guns. The five other bodies only had wounds from other guns.

It's not clear whether any bikers had .223-caliber rifles.