Detectives warn that a gang of robbers could be operating in the Braintree area.

Police are hunting seven men after four robberies in the past ten days.

The Co-op in Bocking has been robbed twice, while Black Notley Post Office and Thomas Cook in Great Dunmow have also been targeted.

And while detectives keep their options open, they are looking at the possibility the robbers are working as a gang.

Det Con Kevin Collett, of Braintree CID, said: "At this stage of the investigation we are keeping an open mind. It could well be that the men are part of a big gang.

"We haven't had any armed robberies in the area for a while and it seems to be a bit of a blip. But we are taking all the robberies very seriously and are very keen to make sure no more happen."

The detective's comments follow yesterday's raid on a Dunmow travel agents. Two men went into the town's Thomas Cook branch and forced three female staff into the back room. One was made to open a safe containing cash and foreign currency.

The robbers are described as between 23 and 25. One is black, six feet tall, of slim build with very short cropped hair, and wore a black roll neck and black trousers.

The other robber, who wore a black stocking over his face, is described as of Chinese appearance and of stocky build, around 5 ft 9ins tall, with black hair and a moustache.

Det Con Collett added: "We would like to hear from any members of the public who see anyone hanging around or anyone in vehicles to let us know.

"Even if it seems to come to nothing, we would still like to hear from people. Often robbers will check a place out only to return days or weeks later to carry out the raids."

Anyone with information should contact Braintree CID on 01376 551312 or Crimestoppers on 0800 555111

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