A GANG of sadistic killers were jailed for life today for their prolonged attack on a vulnerable disabled man.

Brent Martin, 23, was punched, kicked, butted and stamped on during an ordeal last August which stretched one-and-a-half miles across the Sunderland housing estate where he lived, Newcastle Crown Court heard.

The victim's family cheered as Judge John Milford jailed ringleader William Hughes, 22, from Sunderland for a minimum of 22 years, while accomplices Marcus Miller, 16, will serve at least 15 years and Stephen Bonallie, 17, at least 18.

Mr Martin was picked on by the drink-fuelled gang for sport after they bet each other to knock him out for £5, the court heard.

They chased their vulnerable victim around the Town End Farm estate, just three months after he was released from a psychiatric hospital where he had been staying due to his learning difficulties.

Hughes, a father of two from Washington Road, and Sunderland and Miller from Baxter Road, pleaded guilty to murder at a previous hearing.

Bonallie denied the charge but was convicted by a jury at Newcastle Crown Court.

Judge John Milford lifted a ban on identifying the two teenage killers today, who were guilty of sadistic conduct on an extremely vulnerable victim.

After Bonallie's trial, the judge asked Northumbria Police to compile figures on the number of homicides committed by under 21s in the past five years, compared to figures a decade ago.

Toby Hedworth QC, prosecuting, said between 1992-7 in the Northumbria Police area there were 32 homicides committed by people under 21, four by under 17s.

He said between 2002-7, there were 63 homicides by under 21s, with 13 killings by under 17s in the Northumbria Police area.

The judge said the figures for under 21 killings had risen by almost 100 per cent and by under 17s by 300 per cent.

"These are extremely concerning statistics, even if the figures for this particular region are well below figures in other areas and detection rates here are higher," he said.

He said he considered setting deterrent sentences on the three because of the sadistic nature of the attack, but decided to stick to the guidelines set out in law.

Sentencing, the judge said: "I would hope the minimum terms imposed upon young offenders are sufficiently long to spell out to young people the consequences of committing murder.

"If I be wrong then perhaps the 12-year starting point for those under 18 needs to be looked at again by Parliament when the murder is, as in this case, particularly serious."

Judge Milford said their victim was a gentle and caring person who had a long history of mental health problems and learning difficulties.

When he left in-patient hospital treatment in May last year, he looked for friends his own age in the area.

Sadly, he made poor choices, the judge said.

The £3,000 he had saved during his nine years in hospital was quickly spent, mainly in trying to buy friends.

The court heard Mr Martin wanted to befriend the gang, but they turned on him savagely.

The judge was convinced Hughes, the eldest, was the ringleader.

He started the violence, telling Bonallie to catch Mr Martin when he ran off at one point, and delivered the last blow when he kicked his victim who was by this time lying unconscious on the floor.

In a final indignity, the yobs pulled down his trousers and pants.

The judge told them: "You seemed in a state of some elation and went on with your lives. He died from his head injuries."

Mr Hedworth said: "They behaved like a pack of animals as they repeatedly punched, head-butted, kicked, stamped on Brent Martin, who never lifted an aggressive finger towards one of them, and they did so until he was dead.

"They did so for their own sport."

Miller and Bonallie were trained boxers, who knew the force of their actions, the court heard.

Indeed, the three boasted of their prowess and egged each on to knock Mr Martin out, with £5 bets.

Even after being beaten, Mr Martin would shake hands with his attackers and say they were his friends.

One 13-year-old witness said: "I thought once they nutted him out they were going to leave him, but they never. They carried on hitting him and hitting him."

But one final attack, involving being hit against a car so it dented, then a volley-kick from Hughes, eventually proved fatal to Mr Martin.

He suffered catastrophic brain damage and died in hospital, surrounded by his family including his mother Brenda and twin sister Danielle.

After their violent frenzy, the trio posed for pictures and appeared proud of what they had done.

Ben Nolan QC, defending Miller who has an IQ of 79, blamed the availability of cheap alcohol.

He said a common denominator in many young homicide cases was severe intoxication.

Alcohol is readily available at all times of day and night at a ridiculously low cost, he said.

Young people can buy alcohol unscrupulous sellers who can be contacted by mobile phone he said.

"Bottles of vodka are available for as little as £6-a-litre," Mr Nolan said.

"I calculate that to be 30p a double shot."

Mr Martin's family cheered from the packed public gallery when they heard the lengthy sentences imposed.

They walked out of the court building wearing white t-shirts with his name and face on the front above the word 'murdered'.

As well-wishers popped champagne, Mrs Martin said: "I'm just very pleased with the verdict.

The judge was brilliant.

"The Government has to listen to murder victim's families."

Outside court, Det Supt Barbara Franklin, who led the investigation, said she hoped the family would be satisfied with the sentences.

She shared the judge's concerns about violence committed by young people.

She said: "Although weve reduced violent crime in Northumbria over the last 15 years, our research has shown an increase in homicides committed by people under 21.

"We will take robust action against this.

That's why we've invested so heavily in recent initiatives to combat drunkenness and violence, which can often lead to someone being badly hurt or killed.

"Our aim is always to nip violent disorder in the bud before it turns to tragedy."

She blamed alcohol as a major factor.

"It's up to retailers to make sure it's sold responsibly, it's up to parents to take responsibility for what their children get up to outside the home, and we need people to tell us when disorder is happening in their communities so we can take effective action before it gets out of hand.

"I must stress that for a large urban force our homicide rate is much lower than other similar forces, and our detection rate is extremely high.

"We also don't have the kind of gang culture which features in other areas.

"However, all the statistics in the world are of no comfort to those who have lost someone close.

"That's why we move heaven and earth, using all the investigative and technical expertise at our disposal, to track down killers, bring them to justice and get them behind bars.

"That's what happened here today to Brent Martin's killers."