A body has washed up on Muriwai Beach, north-west of Auckland, this afternoon.
No formal identification has been completed but police believe it is the body of a 24-year-old man who went missing at south Piha Beach on Saturday.
Formal identification and a post-mortem will be carried out tomorrow, police said.
On Saturday, a police spokesman confirmed a man aged in his 20s disappeared near Lion Rock at Piha, and a second swimmer needed medical treatment from surf lifesavers in the incident just after 6pm.
St John later confirmed the second swimmer had minor injuries and was not taken to hospital.
A Surf Life Saving spokeswoman said both swimmers were men and got into trouble after being caught in a rip.
"Public raised the alarm with lifeguards at 1750 hours on scene and an IRB was launched. Lifeguards from Piha Surf Life Saving Club and United North Piha lifeguard service were involved in the search.
"One person was rescued by Piha lifeguards upon arrival. One male in his mid 20s is still missing. The on-water search carried on for over an hour in extreme conditions."