A flurry of shots rang out Wednesday evening on a commuter bus, killing one man and injuring another, police said.

Ten to 15 shots were fired on the Milwaukee County Transit (search) bus while it was traveling on the city's north side. The driver stopped the bus and called police.

"The bus driver said, 'I'm driving and then the shots rang out and then everybody's piling off the bus,"' said Milwaukee Police Capt. Eric Moore.

Moore said only one person remained on the bus when police arrived, a 42-year-old man who died in the shooting. A 22-year-old man who was shot in the leg was found outside the bus, Moore said. He was being treated at a local hospital.

Police were combing the bus Wednesday night for clues. "We don't have a motive for the shooting," Moore said.