A 21-year-old man is in life-threatening condition after he was struck by a vehicle while riding a longboard in Georgetown early Friday morning.

Halton Regional Police said the man was hit by a vehicle that was making a left-hand turn at the intersection of Mountainview Road North and River Drive shortly before 12:40 a.m.

The man, a resident of Halton Hills, was airlifted to Sunnybrook Hospital in Toronto with serious injuries.

The vehicle was being driven by a 19-year-old Halton Hills woman, who stopped the vehicle and remained at the scene, police said.

Halton Regional Police Service's collision reconstruction unit is investigating the incident to sort out the circumstances and to determine whether charges are warranted.

Anyone with information is asked to call investigators at 905-825-4747.