Police recover three road motorbikes that were in Prescot on night of Adam Ellison's murder

Speaking on the first anniversary of the 29-year-old’s death, Detective Chief Inspector John Middleton, who is leading the investigation into the unsolved case, said the vehicles had been found “sprayed black quite crudely” after being sold on.

This has led the investigation team to suspect that the large green and white off-road Kawasaki motorbike – which the attacker who stabbed Adam was a passenger on – may have also been disguised with similar paint.

• The passenger who stabbed Adam had been on a motorbike like this

It was among five motorbikes travelling around Prescot town centre in a group in the early hours of Saturday, November 4, 2017, when Adam was killed.

Police – who have today made a fresh appeal for information to break a wall of silence surrounding the case – believe finding three of those is a significant development.

But the Kawasaki used by his killers has still to be traced.

Adam was stabbed after a night out with his cousins where they had discussed how he would propose to his girlfriend Rebecca Cunliffe.

He was an innocent, hardworking young man – employed at the nearby Tesco – who detectives say was simply in the “wrong place, at the wrong time”.

Adam Ellison

Two men on the Kawasaki narrowly missed hitting Adam and his cousins, who had been walking home after leaving The Deanes House pub, at the junction of Market Place and Eccleston Street, Prescot.

The group shouted at the motorcycle which had driven about 50 yards down the road. Adam went over and spoke to the passenger. But the passenger lashed out and inflicted a fatal stab wound before fleeing with the rider.

Over the past 12 months the investigation has seen several arrests but the suspects have all been released and the investigation has continued.

Detectives have also trawled through “hours and hours” of CCTV and interviewed a large amount of witnesses, including a woman who they appealed to find during a Crimewatch appeal earlier in the year.

DCI Middleton today insisted progress is being made but that the nature of the case means it is a lengthy, painstaking investigation.

But he also added that the inquiry needs to overcome “the no grass culture” that police believe is leading to some people in Prescot and Liverpool sitting on potentially vital information because they fear coming forward.

He said: “I think there are people in the community who know who were on those motorbikes that night.

“(But) People are frightened of coming forward because of a (perceived) personal risk.

“I would say whatever information given to us will be treated in confidence and we have ways of protecting people.

“There is this ‘no grass’ culture that we have to overcome. In a case like this it is an innocent young man, Adam, walking home from the pub.

"It isn’t organised crime.

“So I would like people to search their consciences and if they have any information to come forward.”

He urged the community to overcome the fear factor and put pen to paper.

DCI Middleton added: “It has been really hard listening to how this has impacted on the lives of Adam’s family.

“I’m just asking people that whatever their fears of retribution of being called a grass they overcome this for the sake of Adam’s family.”

Anyone with information can Merseyside Police on 101 or Crimestoppers, anonymously, on 0800 555111.