A boy reportedly missing in the water at Sumner in Christchurch is feared dead.
Two boys, understood to be in their early teens, went swimming at Scarborough Beach opposite Burgess St this afternoon.
However, as one of the boys got into trouble, his friend swam to shore to raise the alarm.
A large-scale search between Coastguard and the Sumner Surf Life Saving Club was launched at 3.20pm.
A Coastguard boat was launched, a helicopter searched from the air, while the surf lifesavers put three IRB boats along with nine lifeguards into the water.
However, the surf club called off their search just after 5pm. Police said they were still searching but their efforts had been scaled back.
A spokesman for the Sumner Surf Life Saving Club said there was a southerly drift in the warm, blustery nor-west wind that had pushed the teens around 150m down the beach.
The drift on the outgoing tide had got a few beachgoers into trouble this summer, he said.
The Coastguard referred enquiries to police who were also at the scene.
The boy was believed to be in his early teens, but an exact age hasn't been confirmed.
National Surf Life Saving NZ manager Allan Mundy said patrols had not been operating at the beach today due to the patrol season ending two weeks ago, but an emergency call-out was issued just after 3pm.
He said the IRBs had been called in for the night and would resume the search again tomorrow.
One local woman who did not wish to be named said there had been a huge search effort.
"There a helicopter going up and down the beach, and boats looking all around, behind the breakers, but it doesn't look good now," she said.
There were still a lot of surfers and swimmers enjoying the waves his evening.