The search area for Rory Phimister now stretches from Hampden to Queenstown.
Mr Phimister has not been seen since Thursday afternoon and police have concerns for his wellbeing.
Sergeant Nathan White, of Dunedin, said yesterday the 34-year-old might have been under stress and had some history of health issues.
Public sightings of Mr Phimister so far have included reports of him walking along State Highway 1, south of Hampden.
Inquiries suggested Mr Phimister was in the Queenstown area, Sgt White said.
A search of the Hampden area had been scaled back.About 30 people were involved in the search from Dunedin and Oamaru, while others were working behind the scenes, Sgt White said.
Police are appealing for members of the public to come forward with any sightings or information about where Mr Phimister could be.
Mr Phimister was last seen in Hampden wearing a grey T-shirt, blue jeans and Converse-type shoes with a white toe cap.
Phone Dunedin police on (03) 471-4800.
