Opponents have described it as barbaric and the human equivalent of cock fighting. But the craze of ultimate fighting, which has been sweeping across America drawing thousands at venues around the country, is to descend on Britain.
The combatants lock horns in an octagonal cage, surrounded by a 1.5 metre (5ft) high fence, and once battle is under way it is virtually a case of anything goes as they attempt to punch, kick, slap or wrestle their way to victory.
The first ultimate fighting contest to take place in Britain will be held in July in the Royal Albert Hall, with spectators seated around the cage watching bare footed and bare knuckled American and British fighters battling it out.
There will be a total of five fights, each lasting for five five-minute rounds. The event is to be screened on Sky Box Office, drawing widespread criticism from doctors' groups and politicians, who say caging fighters and allowing them to use karate, kung-fu, boxing and wrestling against each other is brutal, dangerous and should be banned.
Some critics have called ultimate fighting "street fighting in a ring". Events across America regularly draw crowds of up to 15,000. Many ultimate fighters in America have turned professional.
Ultimate fighting was created in 1993. Until two years ago there were only two rules: no striking to the groin or throat and no eye gouging.
Organisers say over the past two years they have introduced new rules, and their sport is as safe as any other.
Bernie Dillon, chief operating officer of Zuffa LLC, which promotes ultimate fighting, said: "It's a real man's sport and our athletes are the gladiators of today. It is the ultimate test of a man. Our athletes are experts in many different fighting disciplines, they train very hard and they care very much for their sport.
"We are well aware of some of the criticisms that have been made against ultimate fighting. It was once a brutal sport but it's not like that any longer. We are very aware of the need for safety and for ensuring that our fighters are medically fit. If you look at our track record on safety, it is as good as any other sports."
The British Medical Association has called for greater regulation, saying there is a danger of combatants sustaining brain damage and other serious injuries.
Bill O'Neill of the BMA said recently: "There is no independent regulation of this activity. There is clearly an intention to inflict injury on one's opponent and that includes serious and significant brain damage."
Some MPs have said they will raise the matter in parliament, and believe the Albert Hall event should not be allowed to take place.
The Labour MP Derek Wyatt, a member of the parliamentary select committee for sport, said: "This is a ghastly sport, if you can call it that. I am totally opposed to it and will raise the matter in the house.
"The fighters who are coming from America should not be allowed to come. We have been campaigning against fox hunting, bear baiting and cock fighting and this is the human equivalent."
Profile: 'You have to be aware of the risks'
As a youngster, Leigh Remedios used to get into a lot of fights, and he admits that he quite enjoyed "giving someone a good hiding". As an ultimate fighter, aged 26, he claims that it is the thrill of winning in style rather than the satisfaction of beating somebody up that drives him on.
When Europe's first ultimate fighting competition takes place at the Royal Albert Hall in July Remedios will be one of three British fighters to take part. He claims that the sport could eventually enjoy a large following in this country, as it does in the US, because it combines the best of many fighting techniques.
Remedios spent almost three years in America and Canada attempting to make it as a full time fighter but confesses that he had trouble making a living. He returned to Britain three years ago and has just completed a degree in electronics at Kent University and is now working as an engineer.
"A lot of people think that ultimate fighting is barbaric and that it is strictly for stupid people but that is not the case at all," he said. "I used to get into a lot of scraps as a kid and started learning all kinds of different disciplines, such as kick boxing, judo, karate and boxing.
"When I went to Canada I enjoyed putting all these different disciplines together. There is real technique and skill involved."
Remedios says that his speciality in ultimate fighting is what is known as "submission grappling," which is favoured by lighter, smaller fighters.
"Being a small guy I find it hard to knock opponents out. I try and catch them in a lock or choke until they submit. If you get someone in a good arm lock they can feel that their arm is about to break. Once they feel that they usually give up."
As he prepares for his most high profile ultimate
"If people think it's barbaric, I don't mind. You have to be aware of the risks but people tend to be very cautious when they criticise ultimate fighters, particularly if they are talking to us."
