Animal activists are appalled and bewildered after an aviation security dog that got loose at Auckland Airport was shot dead.
But authorities say they had no choice.
About 16 domestic and international flights were delayed after the dog, reportedly named Girzz, broke free into the airfield at about 4am.
After three hours to trying to catch the canine, airport staff directed police officers to shoot it.
Animal right's group SAFE's ambassador, Hans Kriek, says he is "appalled and bewildered" and that the use of a tranquilliser would have been a simple solution.
"I suppose they didn't have one [a tranquilliser], but that's not an excuse. They said they were chasing the dog for three hours, surely they could've got one from Auckland Zoo.
There were lessons to be learnt, he added, saying the airport had to get a tranquilliser gun.
"There was a non-lethal solution, they were not prepared. We expect that something is now put in place for future incidents, Hans says.
World Animal Protection New Zealand said on its Facebook page it was "deeply saddened" to hear of the death of Grizz.
"Our thoughts are also with his handler. The fatal shooting of a working dog cannot be a last resort',"
But police and Auckland Airport say they had no other choice.
"Unfortunately as a last resort they had to shoot him," an airport spokeswoman said.
The airport said its thought's were with the dog's handler.
Police Inspector Tracy Phillips says officers had been directed by airport staff to shoot the dog.
"This is not an outcome which anyone wanted, and police were only asked to be involved as a last resort," she said.
Explosive detector dogs are employed at airports to sniff out bombs, rather than drugs. Each dog is paired with a handler.