POLICE today retraced the steps of a vicious gang who assaulted two guards before raiding a security van for thousands of pounds of cash.

Detectives hope the move will bring forward new witnesses about the robbery at the Co-op supermarket in Great Harwood last Friday.

The guards, who were beaten, tied up and had hoods put over their heads, are said to be shaken and currently off work. Before collecting the takings from the Co-op they had made a number of other pick-ups in Greater Manchester.

Police have not revealed how much cash was taken, but it is described as 'substantial'. The raid involved four balaclava-clad robbers.

At 1.06pm, one of the guards was getting back into a white Mercedes Sprinter Van after depositing the takings, when the gang struck. He was overpowered and bundled into a white Suzuki van.

The security van, with the other guard inside, was driven to the rear of Mercer Street. The robbers then broke into the safe and fled with the cash.

At 1.15pm, witnesses saw two men running up the rear of Mercer Street and St. Hubert's Street and residents said a white van screeched to a halt at the top of St. Hubert's Road, collected two men and was driven off. Police believe it headed across rough terrain used by cyclists, known as either 'Switch Back Path' or 'Clayton Fields'.

The van was then abandoned in Charles Street, behind the GEC complex, in Clayton-le-Moors. Police want anyone in that area who saw the four men running off or getting into a vehicle to come forward.

The guard left in the security van was freed by residents at 1.25pm, and the other freed himself and alerted police at 1.45pm.

Detective Inspector Jim Elston said: "We are reliant on witnesses in relation to both sightings of that vehicle as it was being driven away from the scene and through the difficult terrain.

"It's likely the persons responsible have put a great deal of planning and preparation into this crime. There is a likelihood the vehicle will have done a practice run in the days or weeks leading up to the offence."

One witness described seeing a man wearing white overalls and a white hat, as if a delivery man, driving the Suzuki van.

Call Crimestoppers on 0800 555 111 or Blackburn police on 01254 51212.