SEATTLE - A 15-year-old Renton boy accused of beating a Metro bus driver unconscious pleaded not guilty Thursday in King County Juvenile Court to assault charges.
Two other boys -- 16 and 17 -- accused of breaking bus windows in the attack early Saturday in Tukwila pleaded not guilty to malicious mischief charges.
Relatives of two of the boys say they were not on the bus and officers arrested the wrong people.
Prosecutors say the 56-year-old driver was beaten for not opening the rear door. A police dog followed a track to a nearby home where the three boys were arrested.
If the 15-year-old is convicted prosecutors will ask for a sentence of a year in jail. The other two face up to 30 days in detention.