Lurie Children’s Hospital on Thursday confirmed its network was accessed by a “known criminal threat actor,” more than a week into a systemwide shutdown of its communication network.

Still, the hospital system said it continues to prioritize patient care, despite the shutdown.

“Our mission for 145 years has been to care for the most vulnerable children in Illinois, and our top priority remains providing safe, quality care to the patients and communities we serve,” said Brian Stahulak, Lurie’s chief nursing officer and chief clinical officer at Lurie.

Lurie is nationally renowned and is the biggest children’s hospital in the Chicago area, with immediate care centers and clinics throughout the suburbs that funnel the sickest and most complex youngsters to the downtown hospital.

Based on “evidence of suspicious activity” and consistent with best practices, Lurie took systems offline on Jan. 31, said Dr. Marcelo Malakooti, Lurie’s chief medical officer. That includes phones, email, its electronic medical records and the MyChart patient portal, where families message with their providers and book appointments.

The remarks at a news conference just outside the Streeterville hospital were the first time Lurie leaders have commented publicly beyond statements on its web site and on social media. The remarks were brief, lasting just a few minutes, and the leaders took no questions.

But they acknowledged the frustration and concern people might have and said they were inspired by their employees.

Lurie officials did not say how long they expected their system would remain offline. A spokeswoman for the FBI confirmed the agency is investigating but declined to answer questions

With no way to call or message providers, Lurie has set up a call center for families to leave messages with an operator. But some parents say their messages haven’t been returned.

Lurie continues to treat patients, but without access to online medical records, they are working on paper and contacting patients through text messages.

Kristen Schorsch covers public health and Cook County for WBEZ.