A Southland forestry block was searched on Saturday as police and family become increasingly concerned for missing man Dale Watene, not seen for a month.
The 40-year-old man was reported missing last month, last seen in the afternoon on April 16.
Police with the assistance of 30 search and rescue volunteers searched the Longwood forestry block.
Police say some areas of interest were identified and further searches are planned.
"As the weeks pass grave concerns for his well-being continue to grow for both his family and Police," Detective Sergeant Chris Lucy says.
Described as thin and tall, Mr Watene had been driving his blue 1996 Isuzu SUV which was later found by police at Holt Park in Otautau.
Anyon with information about Mr Watene's disappearance is asked to call Detective Sergent Chris Lucy on 03 211 0400 or anonymously through Crimestoppers.