There are warnings that helicopter trips to Franz Josef's Glacier are being put in danger by the careless use of drones by tourists.
On Sunday, a Thai man was given formal warning by police after flying a drone directly above the landing pads at Franz Josef's Glacier Country Heliport.
Police also spoke to another person last week for inappropriate flying and were aware of four other sightings by members of the public in the last fortnight.
The manager of the heliport, Vickie Whittington, said she understood that people wanted great photos but it was a matter of safety.
"Well, those three that I know of were tourists, certainly, and they do appear to be unaware of the danger. However it is their responsibility to know the rules before they use their drone.
"So it's disappointing that they don't appear to even be trying to find out."
The Civil Aviation Authority's rules for flying unmanned aircraft include not flying higher than 120m above ground level, not flying closer than four kilometres from any aerodrome and obtaining air traffic control clearance when flying in controlled airspace.