Dozens of school children and a driver have been rushed to hospital after a school bus collided with a truck and rolled down an embankment west of Melbourne.

One teenage girl was flown to hospital, while the truck driver was taken by road after the crash early on Wednesday.

Four adults, 27 other students and the bus driver were taken to hospital as a precaution.

The injured were reportedly taken to hospitals across Victoria, including Melbourne’s The Alfred and 13 students to Ballarat Hospital.

The Royal Melbourne Hospital has confirmed a woman in her 40s, a man in his 50s and a teenage girl are all in a stable condition.

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The bus was carrying students from years nine to 11 at Loreto College in Ballarat, the school has confirmed.

The crash happened near an intersection on the Western Highway at Bacchus Marsh about 3.15am. A Victoria Police spokesman told the ABC the crash occurred amid the clean-up from an earlier incident.

“There was an incident this morning on the Western Freeway here and
we were still in the process of rehabilitating the area when the second collision occurred,” he said.

“The truck has rounded the corner and headed down towards the hill. It has seen the speed reduction signs and the backed-up traffic and collided with the bus, forcing the bus off the left-hand side of the freeway down into the cliff.”

Local resident Ange Greenland woke to the sound of the air ambulance arriving.

She said the crash site was “pretty nasty” and it was distressing that the young girls had to walk up the embankment after the crash.

“They walked up the off ramp to a waiting bus half a kilometre away,” she said. “I really was very angry because I thought if that was mine, if it was my child.

“I could not believe how they were treated”.

A police spokeswoman told 3AW radio station the bus was coming from a school in the Ballarat area and the students were on their way to the airport for a trip.

The students’ parents were asked to stay away from the crash and contact Ballarat police station.

Melbourne-bound highway lanes were expected to remain closed for several hours as emergency services cleared the scene.

-with AAP