Two people have died and two people have been airlifted to hospital, after a boat was swamped while crossing the treacherous bar on Auckland's Manukau Harbour.
A police spokesperson said emergency services were alerted about 3.30pm, after a passing boat found several people in the water.
Five people were recovered from the water.
The three survivors were taken to Whatipu Beach, where paramedics treated them before two were airlifted to hospital by helicopter, and one was taken by ambulance.
Rescue helicopter pilot Dr Cameron Rosie said the survivors of the accident seemed uninjured but were very fatigued after spending hours in the water.
"We've been asked to attend three men who were on the beach at Waipu and we've ended up transporting two of those patients to Middlemore Hospital, they were stable, they'd been in the water for a long time, they were pretty tired."
Dr Rosie said the helicopter transported two of them to Middlemore Hospital about 5pm, while the other person went by ambulance.
It is understood the group had launched their 5-metre boat from Onehunga earlier in the day and had spent about two hours in the water before they were spotted.
The police will investigate the deaths on behalf of the coroner.