A one-year-old boy was airlifted to a Toronto trauma centre after a single-vehicle collision on Highway 401 in Pickering Thursday afternoon.

Ontario Provincial Police said the crash happened around 2:30 p.m. in the eastbound express lanes near Brock Road. A woman was driving with her child in the back seat when the vehicle lost control and struck a highway barrier.

The child was transported by air ambulance to the Hospital for Sick Children with critical injuries. Police later reported that the infant was in stable condition. The driver was taken to a local hospital with minor injuries.

Westbound lanes were also temporarily shut down but have since reopened. The eastbound express lanes remained closed for several more hours as investigators examined the scene.

Police have not yet determined what caused the crash, and the investigation remains ongoing.