A search of 50 kilometres of farmland and bush on foot and an aerial search with a helicopter has failed to turn up any sign of missing man Stephen Walker.
Mr Walker was last seen at his home near Bulls and around 30 police and land search and rescue staff are continuing to scour the Apiti area for signs of him.
The 25-year-old is the brother of Pete and Andy Walker, fan favourites on TV3`s The Block NZ television show, which screened last year.
A blue Suzuki TF125 farm motorbike that Mr Walker was believed to be travelling on was found on Makoura Rd, Apiti.
Officer in charge of the search Sergeant Andy Brooke said police were concerned for his welfare.
"Today we are researching and expanding our search area with the goal of finding Stephen or any signs of where he may be,'' he said.
Mr Walker is caucasian, of medium build, 6 foot tall and has short brown hair. He was last seen wearing a green Swandri, a green hoody, track pants and gumboots.