Emergency services were called to an incident on Manly Street, Werribee Station at approximately 4.15pm.
One woman injured on the bus said that the PTV bus tried to avoid a possible accident with another vehicle but in the process two passengers were injured.
The passengers were treated on the bus for minor injuries. The other vehicle had left the scene.
The bus driver was very shaken and said that an impatient driver had shot in front of him. The driver was very concerned for the kids on the bus at the time.