A 35-year-old man had to be rescued from Lake Taupo last night after running out of fuel on his jet-ski.
Friends alerted the police, after which a helicopter spotted him waving frantically in the middle of the lake. Two Coastguard vessels were then sent to save him.
The man had not told anyone where he was going or how long he would be.
Harbourmaster Philip King said all lake users should have a phone in a waterproof bag and someone ashore who knew their plans.