HAWKESBURY, Ont. -- Four children sustained non-life-threatening injuries after a multi-vehicle crash involving a school bus in eastern Ontario.

Provincial police say officers from their Hawkesbury detachment were called to the scene of the four-car collision, which occurred around 9:00 a.m. Wednesday.

They say a tractor trailer was also involved in the collision.

Police say the bus driver was airlifted to a hospital in Ottawa, four children were hospitalized with non-life-threatening injuries, and an unspecified number of others were taken to hospital as a precautionary measure.

Police did not disclose the age of the children.

A stretch of Highway 34 remains closed while officers continue their investigation into the crash.