The police say they are supporting the distressed family of a 74-year-old man missing since his boat capsized in Manukau Harbour last night.
The man was one of two people on the boat which sank near the harbour entrance at about 5.30pm.
He failed to surface after the capsizing but his companion was rescued by a nearby boatie.
The Eagle helicopter has been searching around where the boat was last seen and the nearby coastline.
Police coastal master Gary Larsen said the Police dive squad had now arrived from Wellington.
"The divers will go and have a look at the area and make sure it's safe to dive, and they'll make the call on that.
"And then they'll dive more than likely the area of the last known position that we located the vessel before it sunk."
Land Search and Rescue teams are due to search of the coastline at low tide later this afternoon.