Several cars were piled up in the crash on Highway 101. (Shaina Luck/CBC)

The driver of a tractor-trailer is facing a charge of dangerous operation of a motor vehicle after a multi-vehicle crash on Highway 101 that sent three children and their mother to hospital on Tuesday.

Nova Scotia RCMP say a minivan and a motor home towing a car had stopped for construction near Windsor. They were just starting to move again when the collision occurred and they were hit from behind by the tractor-trailer.

The impact sent the minivan into the car being towed. A mother and her three children — a six-year-old boy, an eight-year-old girl and a three-year-old boy — were in the minivan and were all taken to the Hants Community Hospital in Windsor, said RCMP.

The six-year-old boy and eight-year-old girl were later transported by LifeFlight helicopter to the IWK Health Centre in Halifax with life-threatening injuries, said RCMP.

The 59-year-old driver of the tractor-trailer, from Montreal, was treated at the Hants Community Hospital for non-life threatening injuries and later released. He faces a charge of dangerous operation of a motor vehicle causing bodily harm.

The man and woman in the motor home were uninjured. Highway 101 was closed in both directions between Exits 7 and 8 for several hours. It reopened at 5 p.m.

The crash happened around 11 a.m. on Tuesday.

An RCMP accident reconstructionist is investigating.