Items belonging to missing kayaker Koyren Campbell have been found on the seabed, police have confirmed.
Campbell, 22, has been missing since his lone kayak was found floating on Wellington's south coast on Sunday afternoon.
He was due back from a fishing trip at 12pm on Sunday, and his unmanned kayak was found later that afternoon with a fresh catch of fish in it.
Now the Police National Dive Squad has discovered items belonging to him in the desperate search.
The discovery raises a number of possibilities, all of which will be assessed, however it also increases police's concerns, police said in a statement.
Searching in the area where those items were found is ongoing, along with searching in the wider area indicated by the Rescue Co-ordination Centre's (RCCNZ) earlier mapping.
The search team included LandSar members, a Royal New Zealand Defence Force NH90 crew, the Wellington Westpac Rescue Helicopter crew, Wellington Coastguard, Police public safety staff and the Police Maritime Unit and Police National Dive Squad.
The searching will be reassessed as weather conditions change throughout the afternoon.
Wellington has been battered by high winds today.
"We continue to appeal to members of the public in the South Coast area including Eastbourne through to Wairarapa, or along the Miramar/Seatoun coast, to be vigilant and on the lookout for Koyren," police said.
"We're particularly interested in speaking to anyone who has come across a life jacket in the greater Wellington area since Koyren went missing."
Police believe the kayak's paddle is also missing.
Anyone with any information that can assist police is asked to contact police via 105 and quote event number P045173862.
Campbell's boss, David Downer from D-Fluff Insulation, was out on Monday on a jetski helping with the search, and said he and other staff hoped to join in the search again over the next couple of days.
Some staff had also been driving up and down the coast on the lookout for signs of him.
"He's just a young, funny guy, you know," Downer said.
"He was just so full of life ... there's nothing bad to say about him."
Campbell, who has been working for Downer for about eight months, walked in off the street and asked for a job.
"He's a brilliant worker ... all the workers are gutted."
Downer said the hardest part was knowing what to say to Campbell's family.
"We've been talking and that, but it's just so hard.
"We're just hoping [the search is] successful one way or the other."
A Givealittle page has been set up by Koyren's friends to raise money to hire a thermal imaging drone to assist with the search.
The drone costs $400 per hour, the page said.
The fundraising page said Campbell is "the most amazing friend" and as of this afternoon more than $6700 has been raised.