Police hunting a gang of ruthless armed criminals say they expect them to strike again within days.

The raiders, one of whom often wears a Saddam Hussein mask, are believed to have struck five times this month in south Buckinghamshire alone.

And police have linked the thugs to attacks in Berkshire, south Oxfordshire and Hampshire.

Eight detectives are working on catching the gang – as well as solving another four unrelated violent robberies which have hit shops this month.

The crimewave means police are having to cope with almost three times the number of commercial robberies they would expect in a normal month.

Some have been frighteningly violent and during the raid on the One Stop Shop in The Green, Wooburn Green, on October 30, a gunman aimed a pistol at a four-year-old girl.

At least three shopkeepers have also been viciously beaten during the raids.

Detective Inspector Philip Chandler, head of operations at High Wycombe CID, said he was confident of catching the gang but added officers had few leads.

He said: "We will crack this case through forensics, eye-witnesses and vehicle details but at the moment we have got very little of any of these three things.

"We have got very few descriptions of their faces. They are wearing masks and we have no real descriptions of vehicles. All we have got is a probable make of the vehicle."

Police were set to widen their appeal for information this week and are hoping to get an appeal on BBC Crimewatch.

Detective Inspector Chandler said: "It is frustrating. I do not like sitting here waiting for another one to happen because that means there is one more victim out there."

And he warned the desperate gang easily resorted to violence.

He said: "They are certainly not averse to whacking people unnecessarily. It is gratuitous. Fortunately nobody has been seriously hurt but I am very worried. It could well be that the next person is seriously hurt."

Police have advised shopkeepers to make sure their video security equipment is working properly and not to resist the gang if they are held-up.

DI Chandler added: "Without putting themselves at risk we are asking victims to try to get details of the getaway vehicle."

Detectives hope the distinctive orange jacket one of the gang has worn will give them their breakthrough.

He said: "The way we are linking them is that the same clothing has been seen and it is quite distinctive. It is a ski-type jacket but it is a make that has not been sold for several years.

"It was worn during the robbery on November 7 and has not been seen since."

Officers have stepped up patrols in village areas at times when the gang is likely to strike.

"There is a huge effort going into it between us and Hampshire and south Oxfordshire.

"We are trying to make our own luck and their luck is going to run out," said DI Chandler.

Police are considering whether the gang could have lived in the area in the past or have links here and are what they are calling "travelling criminals".

A £5,000 reward is being offered for information leading to the the gang's arrest.

Anyone with information should call Criimestoppers on 0800 555 111 or call High Wycombe CID on 08458 505 505