Image: Nine News Melbourne

A bus driver has been killed and dozens of people injured in a crash on the Western Highway at Pimpinio about 2am.

As many as 60 passengers were on the bus when it smashed into the trailers of a B-double truck, which had become dislodged and blocked the road in both directions.

The bus driver died at the scene.

Two of the injured passengers have been flown to Melbourne for treatment.

Three dozen others were taken to Wimmera Base Hospital in Horsham.

The Western Freeway is closed between Horsham and Dimboola.

2019 road toll: 164
Same time 2018: 104