A woman is dead and two children have been airlifted to a Toronto trauma centre after a head-on crash east of Peterborough, Ontario Provincial Police say.

Emergency crews were called to the scene on Highway 7 near Blezard Line just before 2:30 p.m. Sunday.

That's where they say two vehicles collided, leaving a 51-year-old female driver from the Havelock, Ont. area dead.

The driver of the second vehicle suffered non-life-threatening injuries. Two children, including a seven-year-old girl and two-year-old boy, who were passengers in that vehicle, were taken to a trauma centre by Ornge air ambulance with serious injuries.

The area has been closed while OPP collision reconstruction officers investigate.

The cause of the crash remains under investigation and the victim's identity has not yet been released.