Masked robbers armed with a sawn-off shotgun lay in wait for staff to turn up for work before subjecting them to an hour of terror.

A policeman stands guard at the scene

The four balaclava-clad men seized one after another of the nine women and three men as they arrived at the Co-op store in High Street, Chipping Norton, early yesterday morning.

For an hour they held them hostage, tying their hands with tape, until the key holder of the shop safe arrived and was ordered to open it.

The men are believed to have made off with about £30,000 -- takings from Friday, Saturday and Sunday -- as they sped away on two high-speed motorbikes.

A 40-year-old male worker was taken to Banbury's Horton Hospital after suffering a graze to the head during the two-hour ordeal after being hit, possibly by the gun or a baseball bat.

The injured man was last night back at his home in Chipping Norton, being interviewed by police.

People in the town have spoken about their shock and outrage over the raid, which started at around 5.10am.

The bound staff were not released until shortly after 6.30am when other members of staff arrived and freed the hostages before contacting police. Traders in Chipping Norton's High Street told the Oxford Mail yesterday (Monday) that they were horrified to hear of the raid.

Mo Routledge, who works in Top Marks clothes shop, said: "It is dreadful. I can't believe it."

Frances Grey, manager of Sue Ryder Care, said: "We are shocked and horrified. It is quite upsetting. The police came around asking if we had any CCTV cameras which might have evidence on, but we don't."

Adrian Barradell, a spokesman for Mid Counties Co-op, said staff would be offered counselling after enduring an "extremely unpleasant" ex- perience.

He said: "Our personnel team are on hand to meet them as soon as they have given their statements to the police.

"This incident was obviously very serious and distressing, as a number of our staff were tied up and held as part of this robbery."

Police forensic teams were called in to search for clues and the supermarket was closed for the day.

Police area commander Chief Insp Dennis Evernden said the robbers were waiting for the key holder to arrive.

He said: "Unfortunately for everybody, as staff turned up, one by one they were taken hostage.

"They are all very traumatised.

"For this sort of thing to happen is a shock, and it will take a while to get over." He said Chipping Norton had a very low crime rate, adding: "An incident like this has a huge impact on the community."

Ch Insp said he did not know if the shotgun, which was not fired, was used to hit the 40-year-old man.

The robbers fled at high speed on the A361 road out of the town in the Banbury direction.

Police are appealing for witnesses who saw the two motorbikes, each with two riders.

Anyone witnesses are asked to contact police on 08458 505505 or Crimestoppers on 0800 555111.