Eight detectives have been tasked with tracking down the men responsible for two robberies at betting shops and one at a McDonald's restaurant in the space of three days.

The team is examining "striking similarities" between the raids at Betfred in Bretton, on Tuesday afternoon, McDonald's in Eye, on Tuesday night and William Hill in Paston, on Thursday night.

And the officer in charge of the investigation says he is confident the crooks responsible will be tracked down and brought to justice.

Detective Inspector Mike Branston said: "We don't get many robberies of this nature in Peterborough, so to have three in a relatively close proximity in such a short space of time suggests they might be linked.

"Each time there have been two men involved and we have had some similar weapons being used as well, so whichever way you look at it there are some striking similarities.

"At the same time, however, there are also differences, with all the robberies taking place at different times and on two different kinds of premises.

"We have the same team of officers investigating all three to make sure we don't miss anything and the investigation is pointing in the right direction.

"I want to reassure people I am confident we will catch these people and put them behind bars."

The first robbery took place at about 3.30pm on Tuesday when two men held up the Betfred betting office at the Bretton Centre at knifepoint.

At about 11.15pm the same day, two men burst into McDonald's in Crowland Road, Eye, and herded workers into the staff room at gunpoint before escaping with thousands of pounds.

Then at about 9.20pm on Thursday, two men with an imitation handgun stole about £100 from William Hill in Chadburn, Paston.

In each raid, the robbers were described as white men in their late teens to early 20s and had their faces covered with scarves and baseball caps.

Forensic evidence has been collected from all three crime scenes and detectives have also scoured CCTV footage for further clues.

But DI Branston said the most important piece of the jigsaw was likely to come from a member of the public.

He said: "We are still missing that vital piece of information.

"We have got three robberies here where somebody must have seen people waiting outside or running out afterwards, or a vehicle which may have been used in the McDonald's raid.

"We have a CCTV image of one of the robbers, and somebody knows who he is."

Anyone with information should call police on 0845 456 4564 or Crimestoppers on 0800 555111.