Two teenagers have been told to expect to lose their liberty for a “significant period” after they were convicted yesterday of deliberately wounding a vulnerable man.

Matthew Ellis needed emergency surgery on his head after he was struck by a rock, and had his arm broken when he was hit with his own metal detector.

He was attacked by a gang of Asian youths, who pelted him with rocks and stones as he took a short cut home along a path between Frizinghall Community Centre and a five-a-side football pitch on Easter Monday last year.

Mr Ellis, who has mental health difficulties, had been metal detecting in Shipley. Majid Ali, 19, of Aireville Road, Frizinghall, and a 16-year-old Frizinghall boy, who cannot be named for legal reasons, were yesterday found guilty by a jury at Bradford Crown Court of wounding Mr Ellis with intent, after a week-long trial. They had pleaded not guilty.

Neither showed any reaction as the guilty verdicts were announced. Mr Ellis, who was in the public gallery, stared at the floor.

Judge Jonathan Rose agreed to adjourn for probation reports. The pair will be sentenced on August 3 with Amar Shah, 18, of Lynthorne Road, Frizinghall, who changed his plea to guilty during the trial.

Judge Rose told the two teenagers they had committed “an appalling piece of violence towards an entirely innocent and very vulnerable man, as a result of which he suffered quite dreadful injuries and was fortunate not to lose his life.”

The judge said the offence was so serious it was impossible to envisage anything other than a custodial sentence. He said neither would be able to claim credit for their pleas in a trial in which two ten year-old boys had to give evidence. Judge Rose added: “You have had your right to a fair trial. Custody is inevitable.” Ali and the boy were granted conditional bail.

Shah had pleaded guilty on the basis, accepted by the prosecution, that he had used the metal detector to hit Mr Ellis, but had not thrown any stones.

After the trial, Mr Ellis, now 41, said he would be prepared to forgive his attackers if they were to show they were genuinely sorry for what they had done.

Mr Ellis, who is studying for an Open University law degree, said the attack had happened at a time when he was down on his luck, but he was a stronger person for what he had been through.

Mr Ellis said: “They have got to show they are genuinely sorry and wont do that again to me or anybody else.

“They could speak to myself and other witnesses to prove they are sorry.

“I tried to shut it out, but as the trial approached I was apprehensive about giving my evidence.

“The witnesses have been very brave and I thank them.”