A father whose 22-year-old son has been left brain-damaged has condemned as too lenient the 15-month sentences dealt out to four teenagers who attacked him.

Glen Dennis was in a coma for three weeks and now cannot live independently after suffering head injuries on June 2, in an attack in Coach Road, Saltaire.

Today four young men who set about him were sent to a young offender institution.

Twins Jamie Yeadon, of Valley View, Baildon, and Danny Yeadon, of The Acre, Woodside, Bradford, both 19, Michael Brogan, now 20, of The Crescent, Ilkley, and Simon O’Hanlon, 18, of Holme Top Lane, Bradford, pleaded guilty to unlawfully wounding Mr Dennis.

Bradford Crown Court heard that Mr Dennis, who worked at Asda in Shipley, remembered nothing of the incident.

The defendants confessed to family and the police that they surrounded Mr Dennis. He was struck with a branch and set upon with feet and fists.

Prosecutor Mehran Nassiri said Mr Dennis was seen banging his head on the bar counter at The Sun Hotel in Shipley on the night of the attack. A forensic pathologist said the self-inflicted blows could not be ruled out as a contributory cause of injury.

The court heard that Mr Dennis left the bar about 11pm. He was later found unconscious on grassland with bleeding to the brain.

Judge Jonathan Durham Hall QC said Mr Dennis was a hard-working man drinking his worries away that night. He became upset and hit his head on the bar counter. The defendants befriended him outside but then found him drunk and annoying.

After the case, Mr Dennis’s father, Robert Dennis, said he was “disgusted” by the 15-month sentences. “They have got away with it,” he said. “They’ll be out in a second.”

He said it was impossible to say what the future held for his son.