A rescue chopper is responding to a water incident that's left a person critically injured in Te Anau.
The incident was reported at around 4pm and St John confirmed an ambulance attended the scene.
This summer has been worst so far for drownings in New Zealand since 2015, according to Water Safety New Zealand.
As of January 3, there had been 22 drownings across the country since the beginning of December, with another two months to go before the end of the summer reporting period.
Last summer, 25 drownings were recorded across the whole three-month period, which is also the average over the past five summers.