Det Insp Nick Walton, from Queens Road CID, said it was “particularly frustrating” that people who knew the identity of those who delivered the fatal blow had either not come forward or not been fully truthful with the police.

“Mr Weaver was innocently caught up in events,” he said.

“There are people who know who did this.

“We need these people to come forward and provide a statement.

“There are also people who may have spoken to police already who might wish to reflect on what they have previously said.”

Det Insp Walton said measures could be used to protect anyone who felt intimidated into not giving evidence.

Two men, aged 20 and 23, were arrested on suspicion of attempted murder following the incident but later released without charge.

Anyone with information should call police on 0845 113 5000 or Crimestoppers on 0800 555111.