Wellington  - Five people missing in a boat in bad weather off the New Zealand coast for 24 hours were found alive by a search helicopter on Tuesday, rescue authorities said.

A sea-and-air search for two men and three boys - aged 16, 12 and 11 - in a 5.5-metre fibreglass runabout was launched early Monday afternoon when the skipper sent a text message to his wife saying they were lost and needed help.

Coastguard official Tom Scott said four were airlifted to hospital and the skipper and his boat were being towed to port.

The five, whose names were not immediately released, left the small Bay of Plenty settlement of Maketu Monday morning on a snorkelling trip to an offshore island.

Monday's search was curtailed by heavy rain, high seas and strong winds. An air force maritime surveillance plane with sophisticated night vision equipment found no sign of the boat in sweeps over the area during the night. (dpa)