Firefighters have returned to two previously contained wildfires in the Canterbury region after they flared back up.

Fire and Emergency New Zealand said in an update they’ve had reports of flare-ups in two different areas of the fire in Bridge Hill, which had grown to about 980ha over the weekend.

The major fire caused evacuations in Castle Hill Village last Thursday, as smoke spread with fears flames would follow.

On Sunday, however, Fire and Emergency had said the fire was largely controlled and crews remained on site to monitor the perimeter.

“We had one fire crew already on site dealing with a few hotspots and they have called for an extra four fire appliances to assist with these two flare-ups,” it said today.

The wildfire near Canterbury's Castle Hill had spread to 980ha on December 6. Photo / Fire and Emergency New Zealand

Two helicopters have also been dispatched to assist.

Fire and Emergency said in a post online the smoke was visible from State Highway 73.

“If you are driving past, please keep your eyes firmly on the road and not what is happening on the fire ground, we don’t want to be attending to a vehicle accident as well as trying to fight the fire,” it said.

In addition to the Bridge Hill fire, Fire and Emergency said they’re also responding to a flare-up of the fire previously contained at Kirwee.

The blaze started on Saturday, December 7 just before 11pm.

“There are six trucks attending the fire, and two helicopters are on their way,” they said.

They’re urging people to avoid the area where possible.

More to come.