Firefighters are working side by side with DOC to fight a wildfire that's grown to a hundred hectares in the central South Island.

Porter's Pass - a major part of State Highway 73 in Canterbury - has been closed while they battle the blaze.

Fire and Emergency spokesman Darryl Ball says they've got six helicopters and more than 30 ground crews at the scene.

He says the Pass is likely to remain closed all day.

Meanwhile firefighters are making headway on another wildfire in Queenstown.

Ball says the helicopters have gone to ground and they have five crews attacking it from all sides.