A head-on collision south of Ottawa has closed County road 31 in North Dundas.

OPP say it happened around 3:45 p.m. on County Road 31, south of Country Road 13.

Police say two vehicles were involved in the crash.

They say 20-year-old Andrew Jurgens, the driver and lone occupant of a Pontiac Sunfire, was going southbound on County Road 31, when his vehicle crossed the southbound lane, colliding head-on with a northbound Buick Century.

That vehicle was driven by lone occupant Mary Vanderlaan, 80, of North Dundas.

Both drivers were taken to hospital with serious injuries.

A section of County Road 31 between County roads 13 and 43 is closed, with traffic being re-routed. Slow-downs are expected until about 10 p.m.

OPP are investigating.

SD&G OPP, assisted by Technical Traffic Collision Investigators (TTCI) continue to process and investigate the scene.