COBOURG, Ont. - A police officer is being credited with rescuing an elderly man who wandered away from home during the night and fell into a chilly lake north of Cobourg, Ont.

Provincial police say they received a report at about 2 a.m. Thursday that a 72-year-old man with Alzheimer's disease had left his home in Gores Landing sometime after he and his wife went to bed at 10 p.m.

Officers checked the surrounding property and roads, while another officer went to the nearby government dock area at Rice Lake, where he saw the man floundering in the 5 C water.

Police say the officer, Const. Phil Clarke, grabbed a seat from his police cruiser to act as a flotation device, then dived into the water and swam to the man, who was a distance from the shore.

The man was able to hold onto the seat and Clarke brought him back to shore, where the man immediately lost consciousness.

The man was taken to hospital by ambulance for treatment of non-life-threatening injuries.