TALLAHASSEE, Fla. — A major hospital system in northern Florida said Friday it is diverting some emergency room patients and canceling surgeries after a security problem with information technology.

Tallahassee Memorial HealthCare said the issue began affecting its systems late Thursday night and has forced the hospital to shut down its IT network.

It had the hallmarks of a ransomware attack, but the hospital has not yet characterized it as such, instead calling it an “IT security issue.” Victims often at least initially decline to confirm ransomware attacks.

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A statement from the hospital said it has rescheduled non-emergency patient appointments and has diverted some emergency room patients. It said it is not moving patients currently in the hospital to other facilities.

All non-emergency procedures have been canceled and rescheduled, the statement said. It is unclear when systems will return online. The hospital said it has been working with law enforcement.

The hospital, headquartered in Tallahassee, provides health care across 21 counties in northern Florida and southern Georgia, according to its website.

Cybersecurity firm Emsisoft said there were 25 ransomware attacks involving hospitals or hospital systems last year.

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