A police constable is being treated for hypothermia after swimming to the rescue of a would-be car thief who fled into the cold waters of Lake Rotorua.
Police were called to a house in Kawaha Point at about 4am when a home owner caught a man breaking into a car on his driveway.
The alleged offender threatened the home owner with a pipe wrench after being confronted, police said.
An officer with a police dog chased the man 3km through properties and reserves in Kawaha Point before catching him in the backyard of a house near Lake Rotorua.
Police said the man then jumped down a steep bank and into Lake Rotorua, which has a current temperature of about 9.5 degrees.