One of Melbourne's largest metropolitan public health services has postponed some elective surgery procedures after experiencing a "cyber incident".
The incident, which took place late on Tuesday, has forced Eastern Health to pull a number of its IT systems offline as a precaution.
Eastern Health operates the Box Hill, Maroondah, Healesville and Angliss hospitals, as well as a number of health services, including Yarra Ranges Health and Wantirna Health.
In a statement, Eastern Health said it had taken its systems offline while it investigates the incident, but stressed that "patient safety has not been compromised".
Category two and three elective surgery procedures have been postponed, while category one procedures will continue.
"We apologise for the inconvenience this may cause," Eastern Health said.
"We thank our staff, patients and their families for patience during this situation and we will keep them informed."
Update 8:30 pm: Eastern Health said it was continuing to experience "significant impacts related to the cyber incident".