Five Law Lords unanimously rejected their appeals against conviction for the slaying of 16-year-old Tyrone Clarke.

A baying mob cornered Tyrone in Brett Gardens, Beeston and laid into him with baseball bats, poles and lengths of wood before he was fatally stabbed in April, 2004.

The four convicted of murdering Tyrone claimed that because none of them was singled out as the knifeman who caused the teenager's death, the sentences were unsafe.

But five Law Lords have rejected their appeals – a ruling today welcomed by Tyrone's mother.

Lorraine Fraser said that barristers and the police had told her the Law Lords ruling had changed the law on 'joint enterprise' and made it clear that those taking part in an attack which led to someone's death were guilty of murder – even though they may not have inflicted the fatal blow.

Lorraine added: "Those four took my son's life and robbed me of a son and grandchildren. They have never shown any remorse and they are where they belong – in prison. But, no matter how long they are in prison they will still not serve the life sentence I will serve.

"In spite of that, my son's murder has led to a change in the law."

The four who appealed against their murder convictions were: Islamur Rahman, 21, Kamer Akram and Anjum Nisa Amin, both 22, and Liaquat Ali, 17, all of Beeston, Leeds. They were all jailed for life.

Today, Det Chief Insp Mick McDermott, who was deputy senior investigating officer on the Tyrone murder inquiry, said the rulings leave no one in any doubt that they were responsible and were rightly convicted of Tyrone's murder.

"The ruling my the House of Lords does clarify the issue of 'joint enterprise' and according to lawyers, will be regarded as a precedent in future cases," he added.

* Last week, the YEP revealed that a fifth man wanted for questioning over Tyrone's death had been filmed in Pakistan. Qasim Majid is believed to have flown there within days of Tyrone's murder. A man from south Leeds who was visiting Pakistan spotted Qasim in Dina, about 70 miles from Islamabad and secretly filmed him.