A man who attempted to extort GBP1m (US$1.99m) from leading UK retailer Tesco has been jailed for six years.

Philip McHugh was found guilty of sending 76 letters threatening to bomb Tesco stores in the UK last summer. The retailer had to close stores in Yorkshire and Humberside following the threats, resulting in an estimated GBP1.4bn in lost sales. He also threatened to contaminate Tesco products.

The judge at St Albans Crown Court said McHugh, who had become addicted to online gambling and had personal debts of GBP37,000, was guilty of a sustained and serious effort to extort money from the chain.