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Police investigating the tragic drowning of two young children on Anzac Day have revealed that one of the boat's bungs is missing.
Detective Senior Sergeant Simon Scott told TV One News that one of two bungs, which can be removed to drain water from a boat, are missing.
Police are continuing to probe why the aluminium boat sank on Anzac Day, claiming the lives of an Auckland brother and sister.
The Rowles family launch sank in calm waters in Auckland on Tuesday, drowning two children and leaving four adults marooned on rocks.
The 7.3m aluminium launch had just been bought by the Devonport-based family and was on its first outing.
In the early hours of Anzac Day morning, the two children on board, Erina Rowles, eight, and her five-year-old brother Travis, noticed water coming in and alerted the four adults on board.
They started the launch's 225 horsepower engine and headed for a rocky island but the boat sank before they could beach it, trapping the two children in the cabin. The four adults were marooned on the rocks for nearly five hours before a passing vessel noticed them and raised the alarm.
The bodies of the children were recovered about 8.30am on Anzac Day from the sunken launch.
Detective Senior Sergeant Scott said today an inspection of the boat by the Police Maritime Unit at Mechanics Bay, Auckland, had started this morning.
"This inspection is not yet complete and the boat will remain in secure storage for that purpose for the next few days.
"At this stage no conclusions have been reached as to what caused the boat to sink."
Mr Scott said survivors and other witnesses were still being spoken to, a process which would continue into next week.
"Police investigating the matter are sensitive to the family's need to grieve."
A short ceremony was held this morning, which involved the blessing of the boat, he said.
The family were preparing to say goodbye to their children at a tangi tomorrow morning, followed by a burial, on the North Shore.
The children's emotional and grief-stricken father has told how how he and his wife worked desperately to save the children.
Lindsay Rowles, 53, and his wife Tania rushed to their children when the launch began taking on water and sinking off Tarahiki Island, east of Waiheke Island.
Mr Rowles said when they noticed water coming into the boat they lifted the anchor and headed towards the nearby island.
However, before they could reach land the stern sank and the bow lifted before the boat disappeared under the water, taking the children, who were trapped in a cabin, with it.
He told the New Zealand Herald one police theory was that an abandoned anchor rope had wrapped around the propeller and pulled them backwards when the motor was started.
"I think the rope wound us down to the bottom."
Mr Rowles said his wife was struck on the head as she tried to get into the cabin as the launch sank.
"She was hanging onto the kids. It was just so fast," he said, his voice breaking with emotion.
"Tania smacked her head trying to get back in the cabin as it was going down. Lucky we didn't lose her as well."
He said the children's lifejackets may have prevented them from getting out of the cabin.
"We told them just stay where they were until we got close enough, which was too late.
"Should have had them out with me. Should have been on the outside.
"I don't know how I'm ever going to get over it."
He said Erina and Travis were beautiful children who loved "kapa haka, all the sports they can play".
- NZPA
