The Army says it will continue holding live firing training exercises in hot, dry conditions despite sparking two major fires this week.
A fire destroyed 350ha of scrub on training land around the Waiouru base in the central North Island after an exercise by Singaporean armed forces on Tuesday.
And the next day, a major blaze ignited during live hand grenade training at a Burnham rifle range at West Melton near Christchurch.
Acting Chief of Army Brigadier Peter Kelly today apologised for the "disruption and the angst'' caused to local residents by the Canterbury fire.
Live firing has been suspended at West Melton while an investigation is underway.
The police have said arson charges could result if reckless action by the army was proved.
Selwyn District Council principal rural fire officer Wilson Brown estimated the Defence Force would face a bill of about $200,000 for the cost of tackling the fire.
A New Zealand Defence Force spokeswoman confirmed a court of inquiry will be held into its origins.
But in the meantime, live firing will go ahead as planned on other New Zealand military bases.
"Live firing will continue on other bases around NZ based on risk assessment procedures already in place,'' the spokeswoman said.
Defence Minister Jonathan Coleman said he was "very concerned'' by the two fires.