A school bus carrying three children from a special school has overturned in a collision with a hay truck that also flipped.

The crash happened about 8.45am on Thursday on a sweeping bend near the intersection of Warracknabeal-Stawell Rd and Minyip-Dimboola Rd in Minyip, in Victoria’s Wimmera region.

The minibus was on its final pickup run and heading to Warracknabeal Special Developmental School.

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Images taken from the 7NEWS helicopter show the B-double truck on its side, while the bus flipped onto its roof and veered off the road, overturning on the grass.

The female bus driver was trapped and seriously injured.

She was freed with help from Country Fire Authority and State Emergency Services crews and airlifted to The Alfred Hospital.

Horsham Police Acting Inspector Cameron Ross said the students suffered minor injuries and were taken to hospital for observation.

The male truck driver was also taken to hospital and is assisting police.

Ross said early indications suggest speed may have been a factor.

A Department of Education spokesperson confirmed one student was uninjured.

“A bus carrying three students, a staff chaperone and driver from Warracknabeal Special Developmental School was involved in a collision with a hay truck this morning,” the spokesperson said.

“Two of the students were transported to hospital for observation, and the third student is otherwise safe and well.

“Additional wellbeing support is available to students and staff at Warracknabeal SDS, Warracknabeal Secondary College and Warracknabeal Primary School and all families have been informed of the accident.

“Our thoughts also go to the drivers of the bus and truck, both of whom were injured.”

Road closures remain in place around the intersection. Motorists have been urged to detour via Donald or Kewell.