Kaiaua rescue: Dramatic moment as four plucked from water after boat sank on Waitangi weekend

Police have released dramatic footage of a Waitangi weekend rescue operation of four people left clinging to a pillow when their boat sunk.

The gripping video posted on the police Facebook page begins with a desperate phone call on Saturday evening from a stricken boatie treading water in the Firth of Thames without a lifejacket.

Explaining his boat had sunk off the Kaiaua coast, the man urged the police to send help immediately because they were about to lose the phone.

The rescue was recorded from the air, with the Eagle helicopter flying to the spot the group were last heard from. Photo / Supplied

"We don't have any lifejackets and we're hanging on to a cushion," yells out one of the group.

The call ends abruptly with the sound of the phone disappearing under water.

The rescue is recorded from the air, with the police Eagle helicopter flying to the spot the group were last heard from.

The tactical flight officer said the choppy conditions proved a challenge when it came to finding the stricken boaties.

Fortunately, they were spotted, with the Eagle crew finding them close together and no sign of a boat.

"When we first saw them and got a close-up view on our camera system, two were in really bad condition," said the officer.

"They'd taken in gulps of water, trying to get their breath."

A successful rescue mission with the Westpac Rescue Helicopter winching them to safety. Photo / Supplied

He said it didn't look as if they'd be able to tread water much longer.

"It was almost a recovery rather than a rescue."

A decision was made to put a crewman into the water alongside them with rescue gear, while they waited for help.

Because there weren't enough flotation devices, the officer was forced to take off his own buoyancy vest.

The video shows the successful rescue mission, ending with the Westpac Rescue Helicopter winching them to safety.

None of the group needed to go to hospital.