A Scottish health board confirmed it has been the target of a “focused and ongoing” cyber attack.
NHS Dumfries and Galloway said it was working with Police Scotland, the National Cyber Security Centre and the Scottish Government to resolve the matter.
In a statement the health board warned that there is a risk that the hackers have acquired a “significant” amount of data.
It also warned the public that there “may” be some disruption to services as a result of the situation.
Cyber security agencies are investigating what data could have been accessed.
A spokesperson for the health board said they have reason to believe that the data accessed could include “patient-identifiable and staff-identifiable data”.
“Breach of confidential data is an incredibly serious matter.
“We are encouraging everyone, staff and public, to be on their guard for any attempt to access their systems or approaches from anyone claiming to be in possession of data relating to them.
“In any of these situations, contact Police Scotland immediately by phoning 101.”
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