Police are investigating a suspicious fire that tore through vegetation on Cecil Peak, near Queenstown, on Sunday night.
Two helicopters are still at the site of the fire, which began near the shore of Lake Wakatipu shortly after 9pm.
People in Queenstown reported seeing a boat leaving the shore near where the fire began.
Police would like to hear from anyone who saw a boat returning to Queenstown Bay after 9pm.
The rural fire service let the fire burn overnight, before tackling it at first light on Monday morning. It is now under control and the helicopters were due to remain on Monday in order to damp down hotspots.
