Police are calling on Dunedin residents to help in their search for a man missing for four days after leaving a hospital rehabilitation unit.
Gordon McLean, 63, has been missing since Thursday when he left Waikari Hospital, and despite a search team of about 60 people combing the city and waterways, no sign of the man is yet to be seen.
A full review is to be launched into how McLean, described as "frail", was able to leave the rehabilitation unit.
Southern DHB's medical director for mental health, addictions and intellectual disability Dr Brad Strong said they were "increasingly concerned" for McLean's wellbeing.
He said McLean left the rehabilitation unit in which he was receiving care, and has not returned.
Today Detective Constable Donald Peat said the "extensive" search for McLean would continue today.
"Today LandSAR volunteers, Red Cross volunteers, a rescue search dog and police are searching further afield in the town belt," he said.
"They also continue to search Waikari, Helensburgh, Halfway Bush Kaikorai valley and Frasers Gully.
"Police ask residents to check their properties again, particularly in the Halfway Bush area - please check sheds and outbuildings in or around your properties."
McLean was last seen wearing a dark-coloured polar fleece and trousers, a red polo shirt, brown slippers and a black puffer sleeveless jacket.
He is approximately 152cm tall and of very thin build.
Any sightings of Mr McLean should be reported to police immediately on 111.