Image caption Stevie McMullen and Ryan MacDonald were being transported from a Merseyside prison to court

Two men have escaped from a prison van after armed men wearing balaclavas ambushed the vehicle in Salford.

Witnesses reported seeing a car ram the side of the GEOAmey van and men with axes leaving the van with its windows smashed on Regent Road shortly after 09:00 BST.

One man was seen without a helmet on the back of a motorbike as it sped off.

The escaped prisoners are Ryan MacDonald, aged 20, from Salford and Stevie McMullen, 31, from Salford.

MacDonald was on his way to court for sentencing for conspiracy to commit robbery.

Mr McMullen faces charges of conspiracy to kidnap, conspiracy to commit robbery, conspiracy to commit arson, possession of a firearm, and other offences.

The pair were being transported from HMP Altcourse in Fazakerley, Merseyside.

A third man travelling in the van continued on to court, police said.

'Very shaken'

At the scene Ten feet in front of me is the empty white prison van with its windows smashed in. The side door is open, glass covers the ground, the area cordoned off with blue and white police tape. As the commuters inch past in their cars peering out of the windows, many of them will be unaware of the dramatic and daring jailbreak that happened here. In the morning rush hour on one of the busiest roads into Manchester, a gang of men in balaclavas drove their car into the side of the GEO Amey prison van before dragging the driver out of his cab. We now know they helped two prisoners escape, at least one on the back of motorbike. All this a short distance away from Ordsall Lane where Indian student Anuj Bidve was shot in December 2011 and close to where two other prisoners were sprung from a prison van in another breakout in July of that year.

Ch Supt Kevin Mulligan of Greater Manchester Police said Mr McMullen "in particular is someone we need to trace as soon as possible".

He added he did not think the pair "pose a risk unless approached, so it's really important that if anyone sees them they contact us straight away".

Mr Mulligan said one of the men who helped the prisoners escape appeared to have been armed with a sawn-off shotgun, which was used to smash the windscreen of the van during the attack.

The guards in the van were left "very shaken" but uninjured, police said.

The two escapees and three accomplices escaped in a green Saab, which was abandoned a short distance away on Regent Road, near a roundabout at the end of the M602.

Three of the group then ran off into Ordsall and the other two got on to a motorcycle, later found abandoned in Thurlow Street in Weaste.

A 24-year-old man and 28-year-old woman have been arrested in Ordsall, Salford, in connection with the escape.

'Screams'

One eyewitness said he saw a dark green car drive across the carriageway into the side of the prison van.

Image caption The guards in the van were not injured in the attack

"I called the police and then I could just hear the smashing, the screams, everything that was happening," he said.

"I looked back because I could hear some more shouts and there were some men running towards me, so I sprinted as fast as I could into the estate."

A second witness said he saw two men wielding axes and another "appeared to be holding a shotgun".

Mr Mulligan said a "major investigation" was under way and police were "following all lines of inquiry".

"What I will promise is we will return these people to custody," he said.

There was a similar attack on a prison van in July 2011 in the same area.