Police and Navy dive squads have located the engine of a helicopter in Lake Wanaka.
Morgan Saxton, 31, is believed dead after his Robinson R22 helicopter crashed into the south-eastern arm of the lake on Saturday evening.
The search centre says the engine has been positively identified at a depth of 74 metres.
It's the first significant piece of wreckage to be discovered.
The centre says the engine cannot be retrieved by divers, so efforts will be made to attach a line, so it can be pulled up and examined.
Friends of Mr Saxton describe him as a very experienced pilot.
He was on bail pending an appeal, after he and his father, David, were jailed for stealing greenstone from south Westland. They were released from prison in June.
In a statement on Monday, the Saxton family thanked searchers and the public for their help and support.