A number of hospitals and health services in Victoria have had their access to systems blocked by a ransomware attack that took place on Monday.
A noticed published by the state's Department of Premier and Cabinet said that systems in hospitals part of the Gippsland Health Alliance and of the South West Alliance of Rural Health were impacted by the cyber security incident.
At 9:40 AM, when the notice was issued, there were no suggestions that patient data had been accessed.
The attack resulted in servers across the state being "impacted" and as a result access to several systems, including financial management, had been blocked.
"Hospitals have isolated and disconnected a number of systems such as internet to quarantine the infection," the notice stated.
"The priority is to fix all affected systems and prevent any further compromise.
"This isolation has led to the shutdown of some patient record, booking and management systems, which may impact on patient contact and scheduling. Where practical, hospitals are reverting to manual systems to maintain their services."
The state government said it is working with the Victoria Police and the Australian Cyber Security Centre to manage the incident.
During the first year of the Notifiable Data Breaches (NDB) quarterly report, the health services provider industry topped every quarterly report with a total of 163 breaches in 12 months, up to February 2019.
"The Victorian Government’s priority is working with state and federal experts to get these hospitals back online as quickly as possible, so patients can get the treatment they need," minister for health and ambulance services Jenny Mikakos said in a statement.
"A full review will take place to address what has occurred, and identify what additional measures may be required to ensure hospitals have the best protection against cyber security incidents."