The RSPCA's Claire Robinson: "People want to look tough, with a dog that looks tough"
A change in the law is needed to tackle a rise in dog fighting that is leaving an increasing number of animals with horrific injuries, the RSPCA has said.
The existing ban on four breeds was inadequate and the law must "focus back on the real problem... the owner", said the charity's Claire Robinson.
Dog fighting-related calls to the RSPCA had risen 12-fold since 2004, with two thirds involving youths, it said.
Ministers say penalties for dog fighting have been toughened.
The new wave of dog fighting, known as "chain fighting" or "rolling", involves informal fights often held in inner city public parks, says the RSPCA.
"[People] are seeing young people, often gangs of young people, in parks, on estates, some even put two dogs in a lift at the top of the block of flats and will press the button and let the dogs fight until they get to the bottom," Ms Robinson told BBC News.
"Fortunately they are reporting it to us and the police, but often by the time we get there the people are gone and the dogs can't be found."
The RSPCA says a new generation are using rottweilers (left) in dog fights
But one eye-witness who contacted the BBC said he felt complaints to police about dog abuse and fighting were on the increase, but not taken seriously enough.
Teg Davies was on a family trip to the park in Mill Hill, London, to play football with his sons, when he saw three men, "kicking two dogs and throwing them at each other to provoke them".
He says no-one came to investigate, despite a call to local police.
Ministers say there are now tougher penalties for dog fighting and that the new Policing and Crime Bill will make it easier to seize dogs owned by criminal gangs.
But the RSPCA insists the authorities still have limited powers to seize dogs kept by their owners as weapons.
The charity is seeing dogs with "unprecedented levels" of injuries, says the charity's David Grant.
"We see two or three fights most days. At the weekend it can be quite bad - a few weekends ago we had 10", he said.
"We frequently see ears torn off, eyes torn out. In my career as a vet - nearly 42 years - this is the worst it has ever been.
"I have never seen things as bad as this."
The Dangerous Dogs Act, which came into force in 1991, bans four different breeds - the pit bull terrier, Japanese Tosa, Dogo Argentino and Fila Brasileiro.
But NHS figures show dog attacks have tripled since 1991, with many blamed on cross-bred dogs which are not illegal.
Rottweilers or Staffordshire bull terriers were often involved in the "ad hoc" fights staged by gangs of young men in parks, the RSPCA said.
The charity wants the law to focus on people keeping aggressive dogs as a status symbol or weapon, with more checks on owners and stiffer penalties for people mistreating dogs or keeping them for criminal use.
"It's a lot to do with the sort of MTV gang culture - people want to look hard, they want to look tough, with a dog that looks tough," Ms Robinson said.
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