Combatting gang violence: Welcome to Bangkok's real-life fight club

Harsh spotlights and street lamps illuminate a vicious brawl between two furious shirtless men as the screams of a crowd echo beneath a Bangkok underpass: Fight Club Thailand is on.

In the capital city of a country renowned for its highly technical martial arts scene, amateur fighters gather regularly promising to exchange only blood and bruises in the underground club.

While the bout resembles a particularly frenzied boxing match, the setting - surrounded by shipping containers in a poor port-side neighbourhood - is a far cry from the glitzy charms of Muay Thai boxing stadiums.

"Here you don't have to know how to fight. You just need to have heart and that's it," club co-founder Chana Worasart told AFP.

Worasart founded the club in 2016, partly inspired by the cult Brad Pitt movie, to allow amateur fighters to test their skills - or just vent their aggression.

The organisers also believe the club is a way to keep young and aggressive men off the streets and combat gang violence in Thailand. 

"I think the popularity is due to a variety of occupations and fighting styles that are different from the styles in the (professional) ring," he said.

Unlike the movie's famous line banning fighters from talking about their club to outsiders, the Bangkok-based outfit calls itself "the ring that will change violence into friendship".

The group has become a local sensation, with a private Facebook group racking up 73,000 members as word spread of the underground matches.

Fighters are allowed to go all-out in a single three-minute round - with neither a winner or loser declared - but the bouts aren't quite no-holds-barred.

Elbowing, grappling, throwing opponents to the ground and punching to the back of the head are strictly