Liam Cromie, 21, of Waldon Stree, Callon inflicted a single stab wound on David Cornall, 30, as he walked home from the city centre on February 12.

The knife went 13 centimetres into his body causing internal bleeding.

Judge Mr Justice Flaux told Cromie: "Only you know what the motive was for this savage and un-provoked attack."

Bill Cornall, David's father, said: "I hope that Liam Cromie will spend the next 18 years reflecting upon what he has done.

"He should use that time to educate himself so that he can become rehabilitated and of use to society."

Preston Crown Court heard Cromie was a member of the Callon gang.

The judge said "For some time you have terrorised this community in Preston."

Cromie, dressed in a grey Nike sweatshirt stood in the dock at Preston Crown Court Sessions House flanked by four security guards watched by his mother from the public gallery.

Mr Justice Flaux said: "It is quite clear that you habitually carry a knife and that you are not afraid to use it.

"It's difficult to imagine a more cowardly attack as you inflicted on a man who was doing nothing more than making his way home and who seems to have been trying to run away from you."

He added: "You went out on the night in question with other members of the gang armed with knives and weapons and looking for trouble."

The judge said Mr Cornall's death was an inevitable consequence of young men like Liam Cromie roaming the streets with knives and other weapons and that the psychological effect on Mr Cornall's family had been devastating.

He told Cromie: "You have shown little, if any, remorse either in conversations recorded by the police or at the trial.

"I make every allowance for your learning difficulties and other intellectual shortcomings but having observed you throughout the trial it seems you were devoid of normal emotions about the enormity of the trial."

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