Police suspect two men who claimed to own a jetski abandoned off the Waipu coast may have stolen another machine from a nearby property.
A businessman from Langs' Beach has offered a reward for the recovery of his jetski, worth about $18,000, and a trailer that went missing on December 23.
The man and his son were rescued from their jetski, about 2km off the Waipu River mouth, that day after going to check cray pots. The son was dropped off home by a rescue helicopter.
His father was picked up by a Coastguard vessel and taken to the Marsden Pt Marina.
Their jetski was seen drifting along the coast, about 400m off the shoreline south of the Uretiti campground, between 6.30pm and 6.45pm on that day. Circling the jetski at the time was a thundercat boat.
Waipu police Senior Constable Martin Geddes said the boat operators saw the rescue and went out to sea to have a look. When they towed the jetski to Uretiti Beach, they were approached by two men.
The duo claimed the abandoned jetski was theirs and that they'd travel to Mangawhai to get a trailer. They never returned to pick up the jetski.
Mr Geddes said the thundercat boat operator picked up the jetski, washed and stored it in his Waipu home shed.
A second jetski was stolen from the businessman's Langs' Beach home on the evening of their rescue. Mr Geddes said there was a possibility it was stolen by the two men who had earlier claimed to own the jetski.
The stolen jet ski is a 2006 three-seater Yamaha VX Deluxe blue-coloured cruisers with back hulls.
Anyone with information can speak to either Mr Geddes on 09 432 4030, Constable Daniel Hales on 09 432 7719, or to Crime Stoppers.