The New Zealand Defence Force has sent at least 20 experienced firefighters, backed by state-of-the art firefighting equipment, to help battle scrub fires in Canterbury and Hawke's Bay.

Two additional teams comprising about 12 NZDF firefighters were dispatched this morning to help get the fire at Waimarama Road near Havelock North under control.

They have joined the six firefighters who were deployed last night.

Sergeant Ben Lockton, who is leading the NZDF's firefighting crew in Hastings, said the initial crew of six – five from the New Zealand Army and one from the Royal New Zealand Air Force – helped local firefighters for more than 12 hours after arriving last night.

'We were directly involved in fighting the fire and on many occasions were only about 20-50 metres away from the flames. We stayed vigilant because there were big balls of fire as some treetops were engulfed in flames.

'There was a lot of smoke and it was pretty hot. We had brief breaks throughout the night so we could have a quick bite and drink heaps of water. Once we get a few hours' rest we'll be ready to go back to work.”

Three of the Army's new detachable fire pods were being used at Hastings, says Ben.

The pod can be transported on a variety of vehicles and uses an ultra-high-pressure hose with a pointed nozzle that can pierce the ground and douse burning roots.

In Christchurch, three two-member firefighting crews from the Army have been dispatched to help battle a large bush fire that started hills on Monday evening.

Staff Sergeant Jared Davidson, the Fire Master at Burnham Military Camp, said when it was seen how fast the fire was spreading help was offered immediately to the local fire authorities.

'We are ready to assist for the next two to three days at this stage,” says Jared.