Transit detectives are investigating an assault on a bus in Beaconsfield at 1pm on Sunday, July 4, leaving a 53-year-old man with serious injuries.
It is understood a passenger got on the bus on Old Princess Highway before a male passenger was struck by another passenger several times in the head, causing him to lose consciousness.
The 53-year-old man was taken to hospital where he remained for three weeks and required two surgeries.
The offender is perceived to be of Middle Eastern appearance and described as being short, with a stocky build, brown hair and a beard.