Children injured after school bus rolls in crash west of Melbourne

A school bus carrying 45 children has collided with a truck and rolled west of Melbourne.

The crash occurred while the children were heading home from Exford Primary School, near the intersection of Exford Road and Murphys Road at Eynesbury about 3.40pm.

Police say all children have been removed from the bus and are being treated by paramedics, with some taken to hospital.

A dozen people have been transported by ambulance to hospital, including 10 children with serious injuries, and an adult and a child in a stable condition, according to Ambulance Victoria.

Paramedics are assessing a further 25 people at the scene who do not require transport to hospital.

Victoria Police Superintendent Michael Cruse described the damage to the bus as "significant".

"The scene was chaotic," he said.

"We had parents of children arriving on the scene (along with) lots of emergency services.

"The bus has significant damage and is overturned."

Cruse said the bus was attempting to right onto Murphys Road when the truck collided with the rear of the bus.

He said a 49-year-old truck driver stopped at the scene and is assisting police.

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Nicole Kirk's daughter was onboard the bus at the time.

"We raced down here, there was tears and emotion, (my daughter) was frightened, she has scratches, blood on her hands.

"She was more concerned about her friends, she had her seatbelt on and she was fine.

"We are one of the lucky ones."

Eynesbury is located about 44km from Melbourne, near Melton, and the crash occurred near Exford Primary School.

Multiple crews from the CFA, Fire Rescue Victoria, Victoria Police and Ambulance Victoria remain on scene.

Aerial images from the 9News helicopter showed children being pulled from the overturned bus through its smashed windscreen.

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