Arriva is investigating an incident where one of its drivers allegedly punched the driver of a car after a collision.
The incident took place at Xemxija early this afternoon, causing a traffic jam on the route to Mellieha.
"As soon as Arriva was informed, the driver was summoned to its depot where he is being interviewed by the duty manager to establish the facts of the case.
"Disciplinary action will be taken if required," a spokesman for the bus company said.