Customers who used their cards to shop at the Co-operative’s stores on Tuesday may have been charged twice in a “processing error” which hit the company’s food stores and petrol stations. A spokesman said that customers would have the money returned to them within 24 hours. A spokesman for the group said that he was unable to say how many people were affected but it is thought that hundreds of thousands of customers were involved. He added: "We would like to apologise to all those affected, and reassure customers that refunds will be made directly in to their accounts within 24 hours. We will also reimburse any customers who have incurred bank charges as a result of this error. These customers should contact our customer careline.”