Canterbury firefighters have been battling two large scrub fires in the region today.
Motuariki Island near the centre of Lake Tekapo has been engulfed in flames and smoke and firefighters have decided to let it burn itself out.
A Fire Service spokesman said fire broke out on the uninhabited island late last night.
It would be dangerous for fire crews to try and put it out because of burning branches falling from trees.
``It can't go anywhere and it's not threatening anyone so they're just monitoring it from the mainland,'' the spokesman said.
Emergency services were also alerted to a large blaze off State Highway 75 near Birdlings Flat about 2pm.
It was initially feared holiday homes in the area were in the fire's path but they were now not considered to be at risk.
Ten fire appliances were in attendance.