An employee at the restaurant in Crowland Road, Eye, needed hospital treatment after being struck over the head by raiders, who fled with thousands of pounds in cash.

Just hours before the late-night raid on Tuesday, a betting shop next door to a police station in Bretton was held up by knife-wielding thugs for the second time in two months.

As police investigated the possibility the two raids were linked, McDonald's boss Spencer Rollings (32) yesterday praised his staff for reacting calmly to their terrifying ordeal.

He said: "I'm relieved that no one tried to play the hero and put themselves in danger.

"My only concern is for the safety of my staff, and the money is not important.

"They did the right thing by just giving the robbers what they wanted so the whole thing was over as quickly as possible."

The McDonald's raid began at about 11.15pm while a shift manager and four staff were cleaning the restaurant, after closing for the night.

Two white men in their late teens to early 20s burst into the building through the back door wielding a handgun and a wooden bat, and rounded the workers up in the staff room.

During the raid, one employee was struck with the gun before the robbers – who were wearing scarves and baseball caps – ransacked the cash office.

The injured man was treated in hospital for a cut to his head, before being discharged in the early hours of yesterday.

Mr Rollings said: "He took a slight knock to the head, but he is OK. The other lads involved are all fine, but a bit shaken up by the whole experience."

Earlier in the day, between about 3.30pm and 3.45pm, two masked men of a similar description threatened counter staff with a knife at Betfred, at the Bretton Centre, and fled with cash.

The raid comes only weeks after the bookmaker, which neighbours Bretton police station, was robbed of hundreds of pounds by a knifeman on April 22.

Detective Inspector Mike Branston, of Cambridgeshire police, appealed for witnesses.

He said: "We believe a vehicle may have been used in the McDonald's raid, so I would urge anyone who saw a suspicious or out-of-place car or van in the area to get in touch."

Two Peterborough men, aged 18 and 23, were arrested in connection with the Betfred raid yesterday, but were later released without charge.

nAnyone with information can call police on 0845 456 4564, or Crimestoppers on 0800 555111.