Police hunt pair who boarded Melbourne bus and threatened to kill two passengers

Video of two men involved in an early-morning bus attack in Melbourne has been released as police try to identify the alleged culprits.

The victims, two men aged 28 and 22, caught a bus from Swanston Street, Melbourne, about 5.30am on May 24.

Police have been told two other men got on the bus at separate times during the journey and started threatening to kill them, before standing up and challenging them to fight.

The victims sustained minor injuries in the unprovoked attack.

They moved to the front of the bus and waited here until their alleged attackers got off the bus at Moorabbin Railway Station at 6.12am.

The first offender is believed to have been of southern European appearance, aged in his 20s and about 178cm tall with short black hair and a goatee.

He was wearing a grey fedora style broad brim hat, dark coat, light shirt and white singlet.

The other man is believed to be Caucasian, aged in his 20s and about 180cm tall with straight dark hair and a long fringe.

He was wearing a blue baseball cap, dark coat, light shirt and light jeans.

Investigators believe although the duo got on the bus separately, they may know each other.

Police would also like to speak to a young blonde woman seen talking to the man in the cap on the bus.

Anybody with information is urged to contact Crime Stoppers on 1800 333 000.