TORONTO -- One child is in critical condition and another is in serious condition after a multi-vehicle collision on Highway 401 in Scarborough.

Emergency crews were called to the westbound express lanes of Highway 401 near Warden Avenue at around 10:13 p.m. for reports of a collision.

Ontario Provincial Police Sgt. Kerry Schmidt said four vehicles were involved in the crash.

Toronto paramedics said two children were taken to a trauma centre. One has life-threatening injuries while the other has serious injuries.

According to Toronto Fire, both children are under five years old and suffered upper body injuries.

An adult female was also rushed to a trauma centre in serious condition. Another person was taken to a local hospital with minor injuries.

Schmidt said only one westbound express lane is open due to the crash.