Animal cruelty officers broke down while describing the scene of a slaughter of more than 30 dogs after a neighborhood dispute turned violent in New Zealand this week.

Police are investigating the incident, in which 10 adult dogs and 23 puppies and very young dogs were shot dead by two men in a scene described by an animal cruelty investigator as “not unlike a massacre.”

Russell Mendoza is alleged to have confronted his neighbor, Rowan Hargreaves, complaining that one of Mr Hargreaves’ 39 dogs had killed his fox terrier. It is reported that Mendoza then forced Hargreaves to sign a letter agreeing to the shooting of his animals as a result.

Mendoza and another man, armed with a .22 rifle and a shotgun, later returned to Hargreaves’ property in a rural area west of Auckland and shot the dogs in just over 20 minutes.

Eight dogs survived, including four 3-day-old puppies that sheltered an under an adult dog that was killed.

Inspectors from New Zealand’s Society for the Prevention of Cruelty to Animals (SPCA) said that the organization planned to file charges over the killings when forensic examination of the dead dogs was completed.

“I've never seen anything as horrible as this in my life and I cannot begin to imagine the terror these animals were faced with,” Sascha Keltie, an SPCA investigator, said.

“It was a haunting scene of death and destruction and I struggle to comprehend what took place there.”

She said that bullet entry and exit wounds on some of the dogs indicated that they had not died instantly, and blood trails were consistent with an injured dog moving. Another inspector, Vicki Border, said that the shooters seemed to be on a “frenzied mission.”

Bob Kerridge, the executive director of the SPCA, said that the animals would have known what was going on and some would have cowered in fear as others around them died. He said that the case was among the worst his staff had ever seen.

"[The dogs] did everything to protect themselves — they screamed in fear, in terror, and you don't often hear dogs doing that, they knew exactly, their brothers and sisters were being killed around them," he told Television New Zealand.

Hargreaves, whose dogs were not registered, was still in shock yesterday as he described the deaths of his beloved pets.

“If you had your family shot how would you feel?” he told the New Zealand Herald newspaper. “Even though they were dogs, they were my family. Life goes on but it’s not the same.”

It was reported that Mendoza runs a nearby pet shop. He would not comment on the matter yesterday but is believed to be preparing a statement through his lawyer.

SPCA inspectors, who are government appointees, are empowered to file animal cruelty charges under New Zealand law. The men could face up to three years in prison. Police may also lay charges because one of the gunmen did not have a firearms license.