A part of Highway 12 is closed after a serious collision involving a motorcyclist near the township of Brock on Saturday afternoon.

The incident occurred before 1 p.m. on Highway 12 at Brock Concession Road 1.

Ontario Provincial did not say how the collision occurred.

The extent of the injuries is unknown.

The intersection will be closed for several hours while police investigate, according to OPP Sgt. Kerry Schmidt.