Police say a man with Alzheimers is lucky to be alive after falling into a river overnight.
The man, 67, left his home at Ngaruawahia for a regular 6km walk and fell into a cold muddy stream adjacent to the Waipa river.
Concerns for his safety were raised when he did not return on Saturday night.
Police and Search and Rescue squads were on an exercise near Kawhia at the time of the call.
The man was found at about 2.30am on Sunday in a distressed state, sinking deeper into muddy water.
He was taken to Waikato hospital and treated for hypothermia.