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The skipper of a launch that exploded in a fireball off Waiheke Island told last night how he and his two guests were saved by New Zealand's richest man - but had no idea who he was.
Billionaire Graeme Hart, whose $14 million, 40ha property overlooks Church Bay where the accident happened, leaped into his inflatable and rushed to the aid of the three people who had fled the blazing launch about 200m offshore late on Tuesday night.
The notoriously publicity-shy food tycoon arrived in a "massive inflatable raft" before taking the trio - including a woman who suffered serious burns - to Matiatia Bay where ambulance staff were waiting.
But the thankful survivors were in the dark as to who their rescuer was and only discovered his identity later.
"I had no idea who he was - he turned up so quickly that I honestly thought he was the coastguard," said Paul Emtage, skipper of the burned-out boat.
Mr Emtage, a 52-year-old sickness beneficiary from Waiheke Island, said he and two friends had been diving for kina and were returning to Matiatia Bay when the drama happened.
"We were just sailing along and then 'boom' and there was smoke and flames everywhere," he said.
The explosion caused by a faulty gas refrigerator sparked a fire which spread through the boat despite Mr Emtage's best efforts - "I threw buckets of water over it".
A woman inside the boat suffered serious burns to about 10 per cent of her body and jumped overboard. Mr Emtage's friend "Brian", who was steering, also jumped off.
Mr Emtage had minor burns to his face and hands and suffered from smoke inhalation as he rescued his pet labrador, Cess.
After saving his dog, he gathered his friends from the water and the trio set off for shore in a dinghy.
They watched from Church Beach as Mr Emtage's home for the past three years and "everything" he owned went up in smoke and sank before Mr Hart picked them up.
"He just asked us if we were all right and I said we needed to get Leah to a hospital pretty quick.
"I just thought he was a really nice person who was just helping us out - that's what boaties do.
"It's just a pity he didn't have a fire extinguisher to save some of the boat," said Mr Emtage.
Northern Region Coastguard duty officer Katherine Andrews said Mr Hart's quick actions were to be commended.
"If he had not gone out there their burns could have been a lot worse."
The three were flown to Auckland Hospital by the Westpac Rescue Helicopter before being transferred to Middlemore Hospital.
Mr Emtage's dog had burns on her nose and was taken to an animal welfare centre on Waiheke Island.
Howick Coastguard operations officer Bryan Cartelle said the coastguard was alerted just before midnight.
As they headed towards Waiheke, with firefighters on board, they could see the burning boat from about four miles away.
"We could see the fire as we headed across. It was a glow on the waterline."
Waiheke Island fire chief Ron Leonard said when a fire crew arrived the boat had drifted and was "well involved".
It sank shortly after the flames were extinguished.
Although Mr Hart and his Rank Group declined to comment, Mr Emtage said he would pay him back if he could.
"I'm normally down at the boatshed there helping other boaties out if he needs me to do anything for him," he said.