The recovery of two bodies from the wreckage of a plane that crashed into the sea off the Waikato coast on Saturday is likely to be a complex operation.
Police say sonar equipment used by its divers on Sunday has found the wreckage and it appears the bodies of 2degrees chief executive Eric Hertz, 58, and his wife, Kathy, 64, are still with the plane.
The American couple were flying from Ardmore near Auckland to Timaru in the South Island to meet with their adult daughter when their twin-engine aircraft was lost from radar contact just after midday on Saturday.
At a news conference in Raglan on Sunday afternoon, the police said the depth is a difficult dive and the Navy dive squad willl need to be consulted before a decision is made on how to recover it.
Inspector Marcus Lynam said the plane hit the water at high speed and they still need to determine the state of the craft but believe the two bodies are still with it.
"With the plane at 60 metres under water it is very complex, we need to determine what's the structural integrity of the plane in order for us to see if we can get the bodies back as safely as possible."
Inspector Lynam said the recovery will take some time as it is a complex process and a 40-metre exclusion zone is in place around where the plane is.
Searchers' early hopes that the couple might be alive were dashed on Sunday morning, with police confirming that the mission is now a recovery, rather than a rescue.
The head of the operation, Sergeant Warren Shaw, said if the couple had been on the water's surface, they would have been found when searchers found the wreckage 20km from the entrance to Kawhia Harbour.
Eric Hertz's sister Johanna Hertz, who lives in Pennsylvania, earlier said it is a difficult time for her brother's US-based family and they accepted that the situation was not hopeful.
Ms Hertz said Eric Hertz was a wonderful brother, and the couple was devoted to each other and their daughter.
The Civil Aviation Authority said it would send two members of its safety investigation unit to the scene to try and determine cause of the crash.
Spokesperson Mike Richards said the agency would begin its inquiry once police hand over the crash scene.
Mr Richards said the authority has contacted the Federal Aviation Administration in the US as the plane was registered there.
The United States embassy is in contact with police and said its thoughts and prayers are with the Hertz family and friends during this difficult time.
The president of a private pilots' group says Eric Hertz was a very diligent pilot.
Stuart Clumpas from the Aircraft Owners and Pilots Association used to share a hangar with Mr Hertz and said he was very careful about keeping up-to-date with his training.
Mr Hertz was an instrument-rated pilot, which requires additional training and experience, he said.