Three children and an adult remain in hospital after a pickup truck rear-ended a school bus Wednesday on a rural highway east of Halifax.

RCMP say the children and the driver of the truck are expected to recover from their injuries, but no other details were released about their conditions.

The crash happened at 3:45 p.m. on Highway 7 near Oyster Pond, about a hour's drive east of Halifax.

The highway remained closed to traffic for just under two hours.

Photos taken at the scene show that the truck's engine compartment was badly damaged, as was a small section of the rear of the bus, below its rear emergency door.

Police say the cause of the collision remains unclear.