A faulty cash machine in west London has given people twice as much money as they asked for, free of charge.

The machine at a Tesco, in Hounslow, developed a fault for a number of hours which replaced every £10 note they requested with a £20 note.

Queues formed at the machine as the mistake became evident on 13 August.

A spokeswoman for Tesco, which operates the cash machine, said it would not try to recoup the money, adding it was not known how much extra money was taken.

The spokeswoman said: "As soon as we were made aware that one of our cash machines was dispensing £20 notes instead of tens we immediately closed the machine."

She added: "This was thankfully an extremely rare, operational error."