Homes have been evacuated as fire crews battle a large fire that’s been blazing in forest near the Waimakariri River.

The fire, on the Old West Coast Rd near Kirwee in the Selwyn District, has burnt through 80 hectares of pine forest, scrub and farmland since around 10pm last night and is not yet contained.

Seven helicopters and eight fresh crews of firefighters have been brought in this morning to help fight the blaze.

Police evacuated a number of homes last night and many other residents chose to leave as a precaution. Fire and Emergency incident controller Graeme Knight said it appeared no homes had been damaged but an aerial inspection would confirm the situation after daybreak.

Roadblocks are in place, and people are asked to stay well away so firefighters, trucks and machinery can operate safely. Flying drones near the fireground is also banned.

Firefighters have been battling the fire since just before 10pm last night, but it's still uncontained. Photo / Cam Avery

Knight said many people in and around Christchurch would be waking to a lot of smoke this morning.

“We recommend that people who are nearer to the fire ground stay indoors and keep their doors and windows shut to reduce their exposure to the smoke.”

The Canterbury region is in for a scorching hot and windy day with a forecast high of 31C for Kirwee, which has already faced a number of fires this year.

A statement early this morning from Fire and Emergency NZ acknowledged many people would be anxious.

Crews were working hard to protect houses and prevent spot fires.

Initial evacuations had been completed with police also knocking on doors on Old West Coast Rd between Courtney Rd and Robertson Rd to let residents know they could need to evacuate at short notice.

People living outside the evacuation area who felt unsafe at home were also advised to leave.

Firefighters are still working to protect houses and prevent spot fires. Photo / Supplied

A meeting for residents who had to leave their homes would be held at 11am today at the Kirwee Community Hall. An evacuation centre has been set up at the hall by Selwyn emergency management for those who can’t stay with family or friends.

“Smoke from the fire is covering a wide area, including much of Christchurch. If you are affected by smoke, stay inside and keep doors and windows shut to minimise exposure.”

The fire is currently estimated to cover an area of 70 hectares. Photo / Supplied

Fire ‘spreading rapidly, very thick smoke’

A witness last night told the Herald huge pine trees were engulfed in flames within seconds.

Police were evacuating multiple houses in the area as the fire spread and had established a road block, stopping all traffic.

“The wind is blowing strongly and the fire is actively moving towards the coast. It’s spread a good kilometre or more now”.

“It’s spreading rapidly, very thick smoke,” the witness said.

Crews from Kirwee, Darfield South, Darfield, West Melton, Rolleston and Wigram were in attendance last night.