Mr Saxton and his father David were released from Paparoa Prison on bail in June, pending an appeal against their convictions for stealing hundreds of thousands of dollars worth of Ngai Tahu greenstone from south Westland.
Police say the 30-year-old pilot was the sole occupant of the Robinson R22 helicopter reported missing about 8pm last night.
The helicopter was last seen over Lake Wanaka, but an all-night search did not locate it overnight. At 11.15am today Detective Derek Shaw confirmed the person rescuers were searching for was Mr Saxton.
"We remain positive, but realistic and focusing on finding the sole occupant of the helicopter alive."
Twelve search and rescue volunteers were searching an area 10km by 2km at the northern end of Lake Wanaka where some debris had been located this morning.
It was not confirmed the debris was from Mr Saxton's aircraft.
Among those searching for Mr Saxton are Wanaka pilot Toby Wallis, Makarora pilot Harvey Hutton and Te Anau pilot Richard 'Hannibal' Hayes.
Mr Saxton and his father David Saxton (62) were jailed in February when they were found guilty of stealing Ngai Tahu greenstone (pounamu) from South Westland's Cascade Plateau.
David Saxton was sentenced to two years nine months' jail and Morgan Saxton to two years six months.
The men are also respected rescue pilots and are credited with many rescue missions in South Westland, Fiordland and Central Otago.
Their convictions enraged many West Coasters, some of whom protested the jailings.
The pair run Heliventures in the Haast region. The missing helicopter is not believed to be one belonging to the company.
