Water-based search begins for 'frail' man missing in Otago

Gordon McLean has not been seen since 3pm Thursday. Photo/Supplied

Marine search and rescue crews are joining the ongoing search for Gordon McLean, who has been missing from a Dunedin hospital since Thursday afternoon.

Dunedin Marine Search and Rescue have been tasked with checking water ways and culverts in Kaikorai Valley, for the 63-year-old.

About 60 LandSAR volunteers, Red Cross volunteers, a rescue search dog and police were set to continue searching Wakari, Helensburgh, Halfway Bush Kaikorai valley and Frasers Gully today.

Sergeant Richard Panting said police have asked residents to check their properties thoroughly, particularly in the Halfway Bush area. There was concern he may have fallen.

"We will be focusing on searching the properties of people in the areas we did not canvas yesterday. Please check sheds and outbuildings in or around your properties," he said.

McLean was considered very frail and police have serious concerns for his welfare.

He was last seen wearing a dark-coloured polar fleece and trousers, a red polo shirt, brown slippers and a black puffer sleeveless jacket.

The 63 year old is approximately 152cm tall and of very thin build.

Police are following up all potential sightings of McLean which have come in from the public.

Any sightings should be reported to police immediately on 111.