A 16-year-old boy is struggling to stay alive in a Toronto hospital Monday after a harrowing overnight crash on Highway 401.

The boy was a passenger in a Dodge Neon that collided with a white pick-up truck. The driver of the Neon was also treated for non-life threatening injuries while the teen was rushed to Sick Children's Hospital with serious head injuries. The three other passengers escaped without injury.

OPP Sgt. Cam Wooley said police are looking for a tractor trailer that was spotted on the highway in the Keele Street and 401 area at the time of the accident. He said he wasn't sure if the truck was indirectly involved in the collision or just witnessed the incident.

Police closed the highway at the crash scene for a few hours after the accident which happened just after 11 p.m. Sunday night.

Anyone with more information should contact the OPP by calling 416-235-4981 or 1-888-310-1122.