The Scottish Environment Protection Agency (SEPA) has confirmed that an ongoing ransomware attack is likely to be by serious international organised cyber-crime groups intent on disrupting public services and extorting public funds.

In a statement issued Thursday evening, the agency said it was continuing to respond to an ongoing ransomware attack that began at a minute past midnight on Christmas Eve. The security invasion has resulted in the theft of 1.2 GB of data, "equivalent to a small fraction of the contents of an average laptop hard drive".

The incident is subject to a live criminal investigation, SEPA said, as the agency's emergency management team works with the Scottish Government, Police Scotland and the National Cyber Security Centre to respond to "what is complex and sophisticated criminality".

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“Whilst having moved quickly to isolate our systems, cyber security specialists, working with SEPA, Scottish Government, Police Scotland and the National Cyber Security Centre have now confirmed the significance of the ongoing incident," SEPA chief executive Terry A'Hearn said.

"Partners have confirmed that SEPA remains subject to an ongoing ransomware attack likely to be by international serious and organised cyber-crime groups intent on disrupting public services and extorting public funds.”

Initial indications suggest that at least four thousand files may have been accessed and stolen by criminals. This includes business information such as, but perhaps not restricted to, publicly available regulated site permits, authorisations and enforcement notices.

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Procurement and project information, as well as personal information relating to SEPA staff, has also been breached. SEPA said that staff affected to date have been notified.

Priority regulatory, monitoring, flood forecasting and warning services are adapting and continuing to operate, SEPA said.

The agency added that it has been advised, for the time being, to protect the criminal investigation and its systems. As a result, some internal systems and external data products will remain offline in the short term.