POLICE have appealed for two witnesses who could hold the key to solving a robbery outside a Burnley store.

Security guards were targeted at the One Stop Shop, Colne Road, shortly before 5.30pm on Monday.

Police said a gang of three men wearing balaclavas - one armed with a knife - attacked two Securicor guards delivering a cash machine.

One of the victims received minor injuries to his arm and was treated for shock at Burnley General Hospital. No one else was hurt.

Police said a "substantial" amount of cash was stolen.

Detectives now want to talk to a man who walked into a nearby garage and told staff to call police, along with another man who was standing at the bus stop on Colne Road.

Detective Sergeant Derry Crorken said: "This happened at a busy time and lots of people must have seen it. We want to speak to the two men as they may provide the vital piece of the jigsaw."

Detectives have not ruled out a link between the convenience store raid and another on Securicor guards outside Spar, at the corner of Brunshaw Road and Brownside Road, in October when robbers escaped with £50,000.

Police said a similar method was used and that the gangs both appeared to be from outside the area.

Detectives from Lancashire Police's major crime unit were helping Burnley CID look into any links with other attacks in the UK.

In Monday's raid, the gang escaped in a black BMW 325ci convertible bearing false plates, RN52 WBY, driven by a fourth man. It did a U-turn in Colne Road and sped back towards the town centre.

It was later found abandoned on Back Cleaver Street, near to Colbran Street, where the gang changed vehicles.

The crooks were described as white, two were heavily built, around 6ft tall and 30 to 40 years old. One carried a knife and spoke with a Manchester accent, with another smaller in build and 5ft 7ins tall.

Anyone with information should call 01282 425001 or Crimestoppers on 0800 555 111.