CCTV images showing the moment two armed offenders broke a convicted murderer free from prison guards outside a Liverpool hospital have been released.

The images, which have been released to encourage witnesses to come forward in assisting the capture of Shaun Walmsley, 28, – described as a "highly dangerous individual” – and the two men who were armed with a gun and a knife.

Walmsley was serving a 30-year prison sentence for the murder of Anthony Duffy in Liverpool.

The CCTV images show the scene outside Aintree Hospital just after 3pm on Tuesday and a number of potential witnesses in the area at the time.

Police believe they may well have been unaware of what was going on at the time.

Detective Superintendent Natalie Perischine, said: “The CCTV shows that the people involved in the actual incident were in a very close huddle and we know that the although a gun and knife were used by the offenders, they were not blatantly on show to other people walking by.

“One pedestrian is wearing a particularly distinctive tartan or checked jacket.

“These witnesses may not have realised what was going on and may have thought it looked a bit odd, but probably wouldn’t have thought anything of it.

“We do know that the gold Volvo, was blocking the rear of the car which was meant to take Walmsley back to prison, and this was making access to a roundabout at the hospital difficult.

“One delivery driver was forced to mount the kerb to get past and drivers in the vehicles pictured in the stills may also have information which could be vital to our inquiries.

“The CCTV stills also show the clothing worn by the offenders and it may be possible that people who know these individuals may recognise them.

“I would appeal to members of the public to take a close look and if you think you know who those offenders are please call us.

“I would like to reiterate that Shaun Walmsley, and the two others involved in the incident, are dangerous individuals and we will be relentless in our pursuit them.

“We have put significant resources into this investigation and officers are working round the clock with other forces, the National Crime Agency and other police forces and agencies on the continent, and further afield, in a bid to trace him.

“We are determined to find Walmsley and put him back behind bars. And we are also committed to finding the offenders who helped him escape, or anyone who may be harbouring him, so that we can put them before the courts.”

Detectives are advising the public not to approach Walmsley if they see him, as he could be in the company of the others who helped him escape and they are believed to be armed.

Walmsley himself is also described as dangerous.

Officers would ask anyone who has seen Walmsley, knows where he is, or anyone who saw this car in the area, to contact the police on 999, or Crimestoppers, anonymously, on 0800 555111.