Drone crews will be in operation at the Whangamarino wetlands fire near Meremere overnight to identify and monitor hotspots.

The fire has not grown in size throughout Thursday, with aircraft used to extinguish hotspots this afternoon.

Mapping of the fireground will continue and may result in further refinement of the fire size.

Incident Controller Mark Tinworth says ground crews and air operations will again be in action on Friday to monitor and extinguish hotspots.

"Due to the nature of this fire and where it is burning, it will take some time to extinguish it completely.

"Although the fire is still under control, there may still be some visible fire activity from the fire ground and smoke in the area, don’t be alarmed.

"At this stage, ash and debris has been confined to the fire ground."

Fire investigators are continuing to work to determine the cause of the fire.

There will be cordons in place tomorrow on Island Block Road and Falls Road between 8am and 6pm for residents’ access only.

This is the final update for today. The next update will be around 10am tomorrow.

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