Bullets recovered from two bystanders killed during a shootout at a Seattle festival last weekend do not appear to have come from the gun that a 15-year-old arrested at the scene was firing, police said in court documents filed Wednesday. The King County prosecutor’s office filed charges of first-degree assault with a firearm enhancement as well as unlawful possession of a handgun by someone under 18. In a statement supporting the charges, police said the teen was seen firing an untraceable ghost gun into a crowd, but preliminary testing of bullets recovered from two bystanders killed showed they did not match that weapon. Shell casings found at the scene of Sunday’s shooting indicate four weapons were fired during the shootout.