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Australia's largest not-for-profit health and aged care provider has fallen victim to a cyberattack.
St Vincent's Health confirmed in a statement urgent investigations were underway after data had been stolen from its network.
A spokesperson said the health service had took "immediate steps" to contain the breach after discovering the cyber security incident on Tuesday night.
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The spokesperson said the service had also engaged external security experts, and notified all relevant state and federal governments and the necessary agencies.
However yesterday, evidence was found that cyber criminals had removed some data from their network.
"St Vincent's is working to determine what data has been removed," a spokesperson said.
"The investigation into this matter is ongoing.
"Key activities include securing and containing the incident, understanding what the cyber criminals have done, and identifying what data may have been accessed and stolen."
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The spokesperson said the incident had not affected the ability of St Vincent's to deliver the services.
"Our priority is the health and safety of our patients, residents, and our people, and the continuity of St Vincent's services for the community. "
St Vincent's Health offers services in Queensland, New South Wales and Victoria, including public and private hospitals and aged care facilities.
