A shift manager who was jailed for five years "wove a web of deceit", his former employers claim.

Martin Keys, 32, yesterday began his sentence after being convicted by a jury at Gloucester Crown Court.

Keys, who had worked for the Bicester warehouse firm Tibbett and Britten for two years, was found guilty of masterminding a £500,000 plot to steal Mars chocolate bars.

Keys, of Vale Cottages, Wyck Hill, Stow-on-the-Wold, created bogus orders for chocolate while lorries from Birmingham were hired to collect the consignments.

Judge John Neligan told Keys it was clear that he had stolen the confectionery because he was "overcome by greed".

Defence barrister Huw Davies admitted: "He was no Charlie in that chocolate factory."

A spokesman for Tibbett and Britten, which only two weeks ago received an Investor in People award, said Keys was recruited from one of its competitors.

He said: "Given his apparent abilities and track record, he was offered the post of shift manager at the Bicester automated warehouse, a responsible management position. "Regrettably, he chose to systematically abuse the trust placed in him. Martin Keys wove a web of deceit during his two-year period with us.

"Working in conjunction with outside accomplices, he exploited his position to corrupt data and by-pass existing security checks and balances.

"Subsequently, we have adjusted our operating practices and further reinforced our security procedures in an attempt to prevent such a crime happening again."

The spokesman added that it would be inappropriate to discuss the new security measures.

The warehouse and distribution centre, which opened three years ago, employs 140 staff.

It operates exclusively for Mars with an annual turnover of 34 million cases of Mars products, of which eight million are exported to 70 countries worldwide.

Keys' ex-girlfriend, Emma Smiley, 25, of Glebe Court, Duns Tew, was cleared of "laundering" some of the money that he made from the thefts.

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