Thousands of Tesco Bank accounts affected by 'suspicious activity'

Tesco Bank has been forced to block some customers' cards after "suspicious activity" was detected by its fraud prevention system.

Thousands of accounts were reportedly affected after apparent fraudsters targeted the bank's clients, with customers taking to social media to alert the bank.

The bank has alerted affected customers via text message but consumer expert Gemma Godfrey says if you're concerned about your account you should log in and let Tesco know if there's any suspicious changes.

Watch the video above for more advice on what you should do if you're a customer.

Tesco said in a statement: "We have taken steps to protect a small proportion of customers current accounts from fraud following an alert yesterday.

"All our customers can continue to access their account as normal through online banking and can make chip and pin transactions.

:For those impacted, we are working to re-establish a full banking service and we apologise for any inconvenience."