Wearing white gumboots, the handler stands astride his dog in the square pit, slowly tickling its ribs. The American pitbull's neck and shoulders bulge like those of an All Black prop. In the opposing corner stands a dog of similar weight, all muscle and sinew, coat glistening from a fresh wash.

The referee calls "face your dogs" and the handlers place their dogs' front paws behind a line drawn across each corner. At the ref's signal they race at each other like twin Mike Tysons. The dogs meet in the centre, rearing on hind legs. Both lunge for the other's foreleg. One locks on, the other grips his opponent's neck. They wrestle in circles, snarling and tearing at each other, struggling to get on top, for half an hour, an hour, maybe an hour and a half.

The only sound is of snarling and the thud of dog against wall or floor. Owners can encourage their dogs only verbally or by finger-snapping.

The pit walls, once white, are soon smeared with blood. The floor, covered with a tarpaulin, grows slippery with sweat, saliva and bloody paw prints. The white gumboots are speckled with red.

This is the shadowy, paranoid world of dogfighting in New Zealand, captured on video by a policeman working undercover in the drug scene. The footage is rare - filming is banned to prevent identification. The only faces in this video belong to increasingly bloodied dogs.

The venue may be a cowshed or garage - even a country hall has been used, organisers bringing a mobile pit with plywood walls. Those watching are carefully vetted. No one gets in without a nominee.

Police say dogfighting took hold among the gangs in the 1980s. Today it includes businesspeople; betting is part of the attraction. They bet in dope, mostly.

Enthusiasts don't call them fighting dogs, of course, they call them sporting or game dogs.

A game dog is a dog which demonstrates "the combined qualities of courage, aggression and tenacity in the face of utter exhaustion and possible death".

The most popular breed is the American pitbull terrier, bred and trained for gameness. Its close relative the American Staffordshire terrier and, less commonly, the bull terrier, are also used.

The "sport" has its own language, rules, etiquette and gear. A game dog requires not only the right bloodlines but the right training, equipment and diet. It's not cheap, and many own several dogs.

About 1000 people represent the core of this underground blood sport; fringe players and family boost the numbers to around 10,000. Strongholds include Northland, the Bay of Plenty, Taranaki, Wanganui and pockets of the South Island. Enthusiasts will travel the length of the country for a convention - a weekend of fights. Seemingly legitimate clubs and shows provide a smokescreen.

Last week, one of the kingpins of New Zealand dogfighting, Floyd Langkilde, appeared in the Rotorua District Court, charged with breeding and training pitbulls for fighting. To everyone's surprise, he pleaded guilty, avoiding a possible six-month jail term and hefty fine. He was sentenced to 300 hours of community service and was banned indefinitely from owning or taking an interest in dogs.

Based in Kaingaroa, Langkilde was the breeder, owner and trainer of at least five champions, according to his business card. It takes three wins to become a champion; very few are that game. A grand champion wins five fights. Langkilde maintains his dogs' champion status was achieved in agility contests at legitimate shows.

While few fights are to the death - their owners can call a halt by handling or picking up their dogs - most end with both dogs utterly exhausted and when one has no fight left. Dogs may die later of injuries like severed arteries, or they are put down if an obliging vet can't be found. A turn is called when a dog turns away from its opponent, refusing to fight. The dogs go back to their corner, if one refuses to come out - or "stands the line" - the fight is over. A cur - a dog that doesn't want to fight - can be a liability to owner and breeder and risks being destroyed.

Langkilde's success became legendary through underground magazines and newsletters - publicity which would lead to his undoing. His kennel name, Triple D, cropped up in underground publications The Square Circle and The Game Dog as well as the legitimate Pit Bulletin (the newsletter of the Auckland American Pit Bull Terrier Club which he co-founded).

In fight reports, Triple D was frequently named as the handler, trainer or breeder. He lent his dogs to others for breeding and exported litters overseas.

Langkilde was also a judge at "legitimate" conformation shows around the country and was clearly proud of his "Mr Pitbull" status. He wore a hat and T-shirt marked Triple D. His business card carried a picture of a pitbull and read: "Triple D's Connection, home of Ch.Ally, Ch.Spook, Ch.Reggae, Ch.Pye Ch.Crystal." The Ch. denotes a champion.

Under the banner "Show News," the June 1996 issue of The Square Circle carries a report of a fight between CSM's Spook and Clint's Boy. "It is the first fight for both dogs. Spook, a white dog, is conditioned and handled by Triple D. They meet in the middle with Boy grabbing an ear and showing to be fairly clever in defence putting on pressure when given the chance. But Spook is having none of it and he's doing the driving, occasionally catching Boy in the corners, proving himself to be rough with a good mouth.

"But by 18 [minutes] he's getting hot and a turn is called on him. The first handle comes at 25 minutes with Spook going hard, there's two more scratches each, then Boy stands the line at 39 minutes. Spook finishes with a good courtesy. WINNER: CSM's Spook."

Langkilde, 49, of Samoan-European descent, was born in Whakatane and grew up in Kawerau, according to a profile he wrote in 1998 in Pit Bulletin.

"Kia ora fellow bulldoggers," it starts. "I first became involved in showing dogs with a fighting history approximately 18 years ago. It was with Staffordshire bull terriers at which I was very successful, having bred five champions - one of which gained his championship in the States after being exported there.

"I became involved with pitbulls about 13 years ago, purchasing my first one about 11 years ago. My kennel name is Triple D kennels which is widely known for producing some of the best quality pitbulls ever seen in New Zealand both in the show ring and where it really counts."

The July 2004 issue of The Game Dog features an "exclusive" interview with Triple D.

"The inherint [sic] and unyielding will to win is what drew me to the pitbulls. I couldn't help but admire the bravery and undying courage these animals showed even when faced with seemingly impossible odds." In the interview, he says the quality of dogs in New Zealand and Australia is second to none and praises the "hardline" nature of Anzac enthusiasts.

He discusses training and feeding regimens. His dogs enjoy a diet of possum carcasses minced with fruit and vegetable juice, raw green tripe, cooked brown rice and oatmeal.

His dogs spend their first 18 months on a chain. "If they are showing signs of starting I let them take a hold just for a few seconds then take them away. A couple of months later I'll take them off the chain and let them take hold again for about 30 seconds then break them and scratch them." The training increases gradually and the dog is given trial fights (called a roll). "If they show no bad signs and show decent wind and mouth I will take a chance and open them up for a show at between two-and-a-half and three years."

When police and SPCA officers raided Langkilde's home last August, they found many of the trappings of this illegal sport: heavy chains with weights attached; treadmills; spring poles with leather hides attached; breaking sticks, amino acid and syringes. There were seemingly innocuous items like a bucket and sponges used to clean dogs before the fight (to ensure they haven't been coated with drugs which might affect their opponent) and scales used to weigh dogs - for a "fair" fight the dogs should be evenly matched.

They seized registration certificates and export certificates. They took his computer and found email correspondence about matches, articles from dogfighting magazines and photos of muscular pitbulls and potent cannabis heads.

On his lounge wall were old collars and ribbons from legitimate shows. Centrepiece was a picture of his beloved Ch. Ally.

Langkilde is the second major dogfighting figure closed down by Northland-based SPCA inspector Jim Boyd, a 62-year-old retired policeman who founded the Kaimanawa Horse Preservation Society. Boyd's wife Gail is also an SPCA inspector. It's fair to say animal welfare dominates their lives - their kiwifruit orchard is shared with stray cats, adopted dogs, horses, birds and tropical fish.

Both have received death threats, and police at one point told Boyd there was a price on his head. But in his crusade against dogfighting, Boyd has shown the tenacity and courage that Langkilde so admires in pitbulls.

He first heard about dogfighting while still a policeman in the 1980s. He recalls a tip-off that a "show" was in progress at a Headhunters' gang address in West Auckland.

"As we cruised into the street there were all these cars coming out.

"There was a seriously injured dog in there. One of them said his mate had accidentally let one of his dogs out of the car and it had got into his dog. Because the witnesses were the bros we didn't get very far."

As CEO of the SPCA in the 1990s, he realised a longer-term strategy was needed. He obtained a copy of The World of the American Pit Bull Terrier, by Richard Stratton, which delved deeply into dog fighting and training and had it banned as an indecent publication. He later obtained a United States Humane Society manual on dogfighting investigation, now used in the training of SPCA inspectors.

His first breakthrough came in August 2001 when police raided a Far North property for cannabis and were told the crop was hidden under the kennels of some vicious dogs. Animal control officers lacked the legal power to hold the dogs and called in Boyd.

"Every one of them had fresh bite wounds and puncture marks around the legs, shoulder and snout. They would have killed another dog in their vicinity.

"In the garage, there was blood on the walls but none on the floor. I knew they usually put a square of carpet on the floor so the dogs can get traction. When the fight's finished, they roll it up and take it away and most of the evidence is gone."

The owner said he had slaughtered an animal in the garage but swabs from the walls proved to be dogs' blood.

But the first prosecution for dogfighting in New Zealand collapsed when the judge ruled Boyd had failed to properly caution the defendant.

Weeks later came a second chance after another drug raid, at Mokau, near Oakura. Police called Boyd when they found skinny dogs whose owners did not want them let out. Johnson Dale Murphy and Melissa Molly Jane Berryman were convicted of breeding, owning and training dogs for dogfighting and using a place for dogfighting. Each was sentenced to 200 hours community work and banned from owning dogs for three years.

Most of the eight pitbulls seized were destroyed. But one, a stud dog named Mojo, didn't belong to Murphy or Berryman. A few days later Boyd got a call from the owner demanding his dog back. It was Langkilde.

During the court case Langkilde confronted Boyd on the steps of Kaikohe District Court wanting his dog returned. He was wearing a beanie marked Triple D. Boyd recognised the name from dog fighting magazines seized from the Murphy-Berryman property.

He slowly assembled a case against Langkilde, based largely on evidence in the seized publications. More information dribbled in, including a copy of The Game Dog interview with Triple D posted anonymously. "He thought everyone was his friend but some of these people realised pitbulls were getting a bad name because of the antics of dogfighting."

The Langkilde raid and conviction struck at the heart of what Boyd believes is a dogfighting hotbed, stretching from inland Bay of Plenty to Hawkes Bay. But there are other centres and enthusiasts are highly mobile. Boyd cites a convention on a long weekend in the South Island, when a convoy of cars sped through small towns to a village hall, hired supposedly for a wedding function. "They had a Para pool out the back for the kids and a fighting pit in the middle of the hall for the weekend. Whole families are involved."

He is building cases against other figureheads in the "sport" but says he cannot name names.

Boyd hopes the Langkilde bust will have a long-term impact by disrupting bloodlines. Most of the eight dogs seized in the raid, including two stud dogs, have been destroyed. Langkilde, who was sending pups to Australia, is barred from breeding them.

Bloodlines in some New Zealand pitbulls can be traced to the 19th century when fighting dogs were first exported from Ireland to the United States, says Boyd. "These dogs are owned and bred for the purposes of fighting. They are always searching for perfection and are very meticulous in their breeding programmes. Gameness is bred in - this is their sport."

And number one in New Zealand, according to Boyd, was Langkilde.

Despite his guilty plea, Langkilde maintains his innocence.

He told the Weekend Herald none of the seized dogs were fighters, a claim supported by the vet who inspected them.

"They came here looking for drugs, guns, injured dogs, you name it - they basically got nothing.

"If they can say that owning a treadmill means you are training your dog for fighting, then everybody would be guilty of it."

His champions were dogs that gained 100 points at conformation shows in disciplines such as treadmill sprints, weight-pulling and concentration tests, he says.

The magazine articles quoting him and the references to his dogs were from other breeders using his name. He admits the "where it really counts" quote was his, but says it refers to trusting his dogs to protect him if he were ever in danger.

"Boyd is saying that [quote] refers to the dog fighting pit - where's his proof? It's just assumptions. This is coming from a guy that's saying fishing is cruel."

He says dogs were his life and the bloodline of the American pitbull his passion. His kennels had a national reputation among conformation show enthusiasts. "If somebody comes and buys a dog off me I'll ask them what they're going to do with it. But once it leaves my property it's out of my control."

Langkilde says the popularity of pitbulls had waned because of harassment, and he had all but finished with breeding when he was raided.

"I'm not going to say [fighting] doesn't go on. It used to go on - and I stress 'used' to. As far as I'm aware, nothing like that, even remotely close to what Mr Boyd claims, has been happening in New Zealand for a long, long time."

So why plead guilty?

"To get it out of the way. Jim Boyd's an ex-copper with deep pockets and access to the media, out to get somebody on the dole in Kaingaroa. I was going to get arsehole rangers looking over my fence every few weeks.

Boyd: "I want to see the fighting game closed. I don't think it's necessary in this day and age - it's barbaric."

Fight Talk

The world of dog fighting has its own language and rules

Show: A set of matches.
Convention: A major show of several matches, which can last all weekend.
Roll: The controlled pitting of dogs as a training exercise.
Gameness: The combined qualities of courage, aggression and tenacity in the face of exhaustion and possible death.
Game test: Testing the depth of a dog's gameness by rolling until completely exhausted then having the dog prove gameness by scratching to a fresh dog.
Scratch: Rushing across the pit and taking hold of an opponent within 10 seconds (or an agreed count). A method to demonstrate gameness in the pit.
Scratch lines: Lines drawn diagonally across opposite corners of the pit from behind which dogs are set down and released.
Scratch to win: An agreement between owners.
Courtesy scratch: At the conclusion of a match it's desirable for both dogs to continue to show aggression.
Pick up: When an owner concedes a match by picking up his dog. The losing dog is released to make a short no-contact scratch. The owner is then allowed to scratch back.
Turn: When a dog turns its head and shoulders away from the other dog, indicating it no longer wants to fight.
Cur: A dog that doesn't want to fight.