An armed gang which struck at a King's Lynn jewellery shop was still on the run last night as police sought to reassure residents and businesses.

The robbers used sledgehammers to smash their way into a window display at the Francis Wain store on Tuesday morning.

Police have said one of the men was carrying a handgun during the robbery but have yet to reveal what was taken from the store, which is still closed today.

In an update e-mail to residents via the Home Watch scheme last night, Chief Insp Ady Porter said: 'Following [the] robbery at Francis Wain Jewellers, we are keen to reassure members of the public. It was a very unusual event, not only for King's Lynn, but for the whole of Norfolk. We are aware that it must have been very frightening for witnesses and we do appreciate the information and help given at the scene.'

Staff at the jewellery shop are said to be coping well following the raid which lasted under a minute and saw people running away screaming and others finding cover in nearby shops. Asked how the staff are coping, Beth Jex, from Francis Wain, said: 'They are ok but still a little shaken up.

'The police have been great with them and have offered additional help to staff to help them deal with the shock of it all.'

She added: 'It was absolute chaos, but our priority was to make sure our staff were safe and nobody was hurt, which thankfully nobody was.'

She also said the shop's windows had been replaced and it is understood staff will today begin working out exactly what was taken.

Meanwhile, a Big Issue seller has spoken of how he urged people to run away as the robbery unfolded.

The man, who only gave his name as Dane, said: 'I was just eating my breakfast and talking to a mate and didn't even notice the car drive past me and park outside the shop.

'When the alarm started going off, I saw a man with a sledgehammer smashing the glass and the driver started setting off the smoke.

'I was shouting at people to get away because I didn't know if they had a gun or how violent they would be.

'The thought crossed my mind to jump in, but my mate told me not to so I ended up sitting in Marks and Spencer and rang the police.

'It must have been terrifying for the girls in the shop and I just hope they are not too shaken by it all.'

The silver Mercedes people carrier used to carry the armed robbers to and away from the store in the pedestrianised Norfolk Street was found shortly after the raid in nearby North Lynn.

The driver of the vehicle was heard shouting at members of the public during the robbery as he released smoke to try to block CCTV images.

Ch Insp Porter continued: 'Officers are continuing their investigations and are still keen to trace a silver coloured BMW that was seen in convoy with a silver Mercedes people carrier around the area of the town centre prior to and after the incident.'

Police have described the men they are hunting. The first man is 6ft, slim, with a grey two piece tracksuit and hood, with a white scarf covering his face.

The second male is described as 5ft 8ins to 5ft 10ins, of average build, wearing a black long sleeved hoodie, with a grey short sleeved T-shirt over the top. He was also wearing black trainers with white soles and was carrying a small JD sports bag.

Information should be given to officers by phoning 101.