A council was rebuked today for losing an unencrypted memory stick containing the personal details of 40 children in care.
Court reports and details of care proceedings were on the memory stick lost by Stoke-on-Trent City Council, the Information Commissioner's Office said.
The device was found by a member of the public in the Henley area of the city and returned to the council, which has agreed to encrypt portable devices used to store and transmit sensitive personal data in future.
Sally Anne-Poole, enforcement group manager at the ICO, said: "When handling sensitive personal information, particularly information relating to the care of vulnerable children, it is important that authorities ensure the necessary measures are in place to protect this information.
"This incident occurred before April 6 so the powers now available to the Information Commissioner to issue penalties of up to £500,000 for serious breaches of the Data Protection Act, could not be considered."