"This is not an outcome anyone wanted, and police were only asked to be involved as a last resort."
Phillips referred all further enquiries Auckland Airport and Avsec.
A source said police staff and Grizz's handler are "absolutely devastated".
Avsec spokesman Mike Richards said: "All efforts to capture the dog were exhausted and the airport company had no option but to request police to shoot the dog."
"The handler and Avsec are naturally upset but do understand there were no other options, in the very difficult circumstances.
"The dog was not on the tarmac at the time."
Richards said Avsec will now "try and ascertain what spooked the dog and if this has any implications for ongoing training".
It is understood 16 domestic and international flights were delayed as ground staff tried to catch the animal after it broke away from its handler about 4am.
"The dog was clearly distressed and wouldn't let anyone near it so the decision was made to shoot the dog," airport spokeswoman Lisa Mulitalo said.
A police officer killed Grizz, a 10-month-old bearded collie-german short-haired pointer cross, which was in training to detect explosives.
"It had been on the outer perimeter of the airfield.
"It got loose at 4am and we spent three-and-a-half hours trying to catch him. They did everything they could, but unfortunately it had to be shot.
"It's really sad. It's a working dog and they are very important to us at the airport."
A Herald reader poll showed that 60 per cent of respondents did not think Grizz should have been shot.
Another 20 per cent believed the right action was taken and 11 per cent answered "don't know".
National animal rights organisation Safe declared the shooting of Grizz as "needless".
"Safe is appalled about the needless killing of this dog," said spokesman Hans Kriek.
"A tranquilliser gun should have been used after efforts to catch the dog failed.
"If such a gun was not available - which it should - then they could have borrowed one from Auckland Zoo or elsewhere.
"We hope that lessons will be learned from this and that better systems will be put in place to avoid such unnecessary killing in the future."
According to the Avsec website, they employ explosive detector dogs, which are different from Customs and Ministry of Primary Industries' dogs.
"Their job is to sniff for explosives and explosive materials not drugs or food. Each EDD team consists of one dog and one handler," the website said.
"These teams do a very important job protecting travellers, airline crew, airport workers and New Zealand at large by ensuring that no dangerous materials are present on aircraft or in our airports."
They are at the main airports in Auckland, Wellington, Christchurch, and Queenstown.
"Our dog teams search for any explosives in car parks, navigation facilities, unattended cars and unattended items/bags, cargo, and aircraft," the website said.
"They also conduct random searches around the airport environment, at check-in counters, screening points, and gate lounges. By being visible they can act as a deterrent for any wrongdoers."
