PETERBOROUGH, Ont. - Five horses were killed early today when they were struck by a tractor trailer near Peterborough, Ont.

Provincial police say they were among about 15 horses that escaped from a field near Highway 7 and Cameron Line and wandered onto the highway just before 2 a.m.

Police say the driver was unable to avoid the animals and five horses were struck and killed.

The highway was closed until about 6 a.m.