Police are hunting a gang of men who bag up to £800 a night by tampering with fruit machines.

Bingley Inspector David Drucquer said the men use a hi-tech gadget which tricks the machines into paying out.

And he warned members of the town's Pubwatch group, which met yesterday, to be on their guard.

He said: "We have descriptions of up to eight men. It is not known whether they are connected but they probably aren't. We think they are local and may come from the Bingley/Halifax area and are targeting pubs in this area.

"It appears that they enter pubs knowing a code which enables them to win large sums of money. They have a small implement which tricks the computer into thinking that it is due for a big pay-out.

"It is an offence and they would be charged with theft or going equipped. It has not reached huge proportions as yet but it is a problem for licensees and all those in the Pubwatch are now aware of the problem.

"They are making hundreds of pounds out of this and, although I understand from machine suppliers that it is quite common in other parts of the country, it is a new thing in this part of the world."

He advised landlords and their staff to keep a watchful eye on punters playing the machines and urged them to watch out for a series of unbelievably large pay-outs. He said they should call the police if they are suspicious.

He added: "It is difficult to catch them in the act because the implement is very small and can be got rid of very quickly and that is why a very watchful eye should be kept on them."

Bill McDarmont, landlord of The Old White Horse in Bingley, said he had had three different people trying the scam in his pub. He said: "Staff were alert the third time but I think they got about £90. I switched the machine off - it's been a big problem recently."

Steven Croad, a partner with Croad Automatics of Keighley which supplies fruit machines, said: "I have heard that there have been quite a few instances of this in the Brighouse area and a few reports of it in Keighley. A club in Brighouse which barred one person found its takings subsequently went up £200 a month."

Fintan Schneider, of Rank Leisure, explained how the gadgets work. He said: "It sends a high pulse into the machine and basically messes up the computer and makes it drop all its money. "

Dean Harding, of Maygay, one of the country's biggest suppliers of fruit machines, said: "We have had instances of people going on certain machines and sparking the sort of charge that would stun a cow in a slaughter house. Some have blown the machines up.''

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