The New Zealand Defence Force will launch an investigation into yesterday's fire in West Melton.
Live shooting at an army firing range was believed to be the cause on the blaze, which engulfed 50 hectares before it was contained.
New Zealand Defence Force (NZDF) spokeswoman Zen Gregor said the investigation had not been opened yet, but the process to commence the investigation has begun.
"The fire broke out at West Melton while training was taking place. Any investigation will aim to determine the details of the cause of the fire," she said.
"At this time we cannot gauge a time for the investigation to be completed."
Gregor said the army had been training at the range for one week prior to the fire before incident.
"Fire risks are always taken into account and all fire precautions as required by New Zealand Army and emergency service regulations were in place.
"New Zealand Army had fire services at the range while our training was taking place."
One soldier suffered burns as a result of the fire and was treated for his injuries at Burnham camp.
Gregor said whethe anyone was disciplined over the incident would depend on the outcome of the investigation.
All army live firing had been suspended since the incident.
The exercise went ahead despite a fire ban, which allows only permit-holders to light fires.
The fire was put out last night but 25 firefighters were damping down hot spots today.
Canterbury's tinder-dry conditions make more fires a near certainty, authorities said yesterday.
A spell of southerly rain and much cooler temperatures this morning were expected to bring only brief respite to fire crews.
The weather is forecast to stay mostly hot and dry for the rest of the month, and the region would be "extremely lucky" to escape major fires.
The West Melton fire spread despite a fire engine being on standby at the army site because of the extreme risk.
Five properties and the West Melton aerodrome were evacuated as the fire spread northeast and threatened to jump across Weedons Ross Rd.
Five helicopters with monsoon buckets, 16 engines and water tankers battled the fire throughout the afternoon.
New Zealand Defence Force incident controller Sergeant Greg Fagg said the fire started on the range and was soon out of control.
"The fire moved faster than the [on-site] appliance could deal with and it quickly got out of hand," he said.
Displaced residents were allowed to return to their homes last night, but several roads stayed closed overnight as a safety precaution.
Canterbury has been hit by wildfires this year and fire-safety officer Graham Davies said conditions now were as bad as a fortnight ago, when the most devastating fire so far ripped through 150 hectares of farmland at Broadfield, near Prebbleton, destroying two houses.
"We're back to that same situation of hot, dry nor'west winds. The fire danger is extreme at the moment right throughout Canterbury,'' he said.
"It's definitely not going to improve until at least the end of the month. It's going to get worse. We'd be extremely lucky if we didn't [get more fires]."
The prolonged hot, dry weather was unusual, Davies said, even for a Canterbury summer.
"It's been a number of years since we've had such hot, dry conditions. We've had hot days, but not day after day like we had a week ago, and now it's starting again," he said.
Old West Coast Rd resident Fiona Gunn said yesterday's fire and the constant risk weighed heavily on people's minds.
"I've spent since 11 o'clock this morning in some kind of limbo space waiting for something to happen or nothing to happen."
She had packed the car in case the fire reached the large trees that had been cut down around their property and they had to leave quickly.
Fellow resident Amy Grant said the continuing threat was taking its toll.
"It's a rather scary thing since this is the third time now there has been a fire down Thompsons Rd way in the last two to three weeks," she said.
- The Press
Have you seen rats on your property?Related story: Does Christchurch have a rat problem?