A coach driver has died and at least nine people are injured after a bus carrying 60 passengers crashed into the dislodged trailers of a B-double truck on the Western Highway in Victoria.

Police believe the truck was travelling in front of the bus when its trailers dislodged and blocked the highway in both directions, causing the crash and trapping the driver, who died.

The accident happened near Pimpinio about 2am on Thursday, with at least nine people injured, Ambulance Victoria said. The bus was carrying 45 passengers from Adelaide to Melbourne.

A bus driver has been killed after slamming into the trailer of a truck, which became dislodged on a country highway near Horsham.https://t.co/yGZ2oXkQtm — Herald Sun (@theheraldsun) July 10, 2019

Paramedics treated nine people for various injuries, and two were flown by air ambulance plane to Melbourne.

A man in his 40s with leg injuries was flown to Royal Melbourne hospital in a stable condition and a woman in her 60s with arm injuries was flown to the Alfred hospital, also in a stable condition.

Seven other people aged from their teens to those in their 70s were taken to Wimmera Health Care hospital in Horsham after being treated by paramedics. More than 30 other bus passengers will also be assessed at the Horsham hospital.

“We have been extremely fortunate that the people who have been brought in have relatively minor injuries and are stable,” the hospital’s chief executive, Catherine Morley, told the ABC.

“It has, however, obviously been a very traumatic experience for everyone involved and we are caring for patients on all fronts.”

The Western Highway has been closed in both directions, with diversions in place and detectives at the scene.

Anyone who witnessed the crash is urged to contact police.