Dive crews and search teams have not found any sign of a man missing since he leapt from a bridge into the Waikato River in Hamilton on Thursday.
Witnesses reported seeing the man, who appeared to be in his early twenties, leaping from the Claudelands Bridge just before 2.30pm.
They say he surfaced briefly after leaping and then went under the water again.
Police say they are not just worried that the searches have been unsuccessful, but that no-one has come forward who recognises the description of the man.
He is described as Maori, aged in his early 20s, with a limp.
Police are appealing for help from the public.