Steve — not his real name — was praised by animal rights campaigners after his secret recordings of pitbull fight organisers in the Middlesborough and Birmingham areas enabled police to make a number of arrests.

Steve, who received a death-threat from gangsters after he infiltrated the Farmers' Boys dog-fighting gang in Co Armagh for a BBC Spotlight investigation, linked up with the criminals in England after posing as a dog-fight organiser.

As part of his undercover work, the former squaddie took the English crooks to Co Armagh and Finland for a series of depraved dog-fights.

After secretly recording the gangsters buying outlawed dogs and arranging dog-fights for almost a year, Steve passed his information to police.

Although the gangsters have offered a reward to establish the former squaddie's true identity, Steve has pledged to continue with his undercover work.

Speaking to us from his London-based office, he said: "These guys were heavily involved in dog-fighting and I had no problem passing on the information because they were engaged in a brutal sport.

"The people in England were working closely with the Farmers' Boys and they weren't happy when I exposed their mates.

"They were furious because it meant them losing out on huge amounts of money with the dog-fights. I would do it all again if I had to because I'm a strong believer in animal welfare.

"My work is continuing and we should all work hard to get these people before the courts.

"These people are very dangerous, but they're not going to stop me from continuing my work."

Steve's actions were also praised by the RSPCA.

A spokesman said: "Steve is a very brave man who put his life in danger to expose the cruel and vicious sport of dog-fighting.

"He deserves tremendous credit for his undercover work and through his efforts he has helped disrupt activities which brings nothing but misery.

"If it wasn't for people like him, it would be hard for the police to bring these people before the courts and for the public to be made aware of this major problem."

Brave TV hero Steve previously helped Sunday Life unmask the 'devil-dog' dealer Gary 'Skivvy' McGivern.

We snared the convicted hijacker, fraudster and burglar during an undercover operation targeting gangs that bred banned pitbull terriers for illegal dog-fights in 2006.

Along with one of our reporters, Steve posed as a dog-fight organiser from England who wanted to buy a banned American pitbull.

After meeting McGivern we later purchased the dog for just £80.

We then handed the six-week-old pup over to the USPCA to save it from the brutal life of a fighting dog.

USPCA boss Stephen Philpott was also subjected to a death threat from thugs for exposing Northern Ireland's dog-fighting network.

breen@belfasttelegraph.co.uk