The police say deer hunters could be behind a series of fires in and around a kiwi sanctuary just north of Franz Josef on the West Coast.
Twenty hectares have been burnt in six fires since Sunday morning. Four of them were in the Okarito kiwi sanctuary in Westland Tai Poutini National Park, home to 350 rare rowi kiwi.
The Department of Conservation (DoC) says that all have been accounted for since the fires were lit.
The police believe that hunters wanting to encourage regrowth in order to attract deer may be responsible - or it may be someone who has a gripe with DoC.
They are investigating sightings of a red car and a dark green Subaru station-wagon near a fire on Sunday night.
Conservation Minister Kate Wilkinson says it's an absolute disgrace that anyone would deliberately set fire to bush in a kiwi sanctuary, and is calling on locals to keep a close eye on the area and report any suspicious behaviour to the police.