Cyber criminals have stolen "personal or sensitive" data during a ransomware attack on West Lothian Council's education network, the local authority has confirmed.
The council is contacting parents or carers at every school as well as education staff to inform them of the theft and provide advice.
It said most of the stolen data related to operational issues such as lesson planning, but officials have now established that some personal information was also taken.
Confidential pupil records, financial data and social work records are stored on different systems, but officials said they could not rule out the possibility that medical or social work information has been stolen by the criminals.
The council told the BBC there is no evidence at this stage that social work reports have been stolen.
BBC Scotland News understands a group called Interlock has claimed it is behind the attack.
Such groups operate by using malicious software to encrypt an organisation's files, then demand a payment with a threat to publish the material online if no ransom is paid.