World Health Organization Director-General Tedros Adhanom Ghebreyesus said early Monday that Gaza’s beleaguered hospitals “have once again become battlegrounds and the health system is under severe threat.”

Ghebreyesus said the Kamal Adwan Hospital in the north Gaza town of Beit Lahia “is out of service,” following an Israeli raid which itself came after several weeks of encirclement and bombardment.

Israeli forces raided the compound on Friday, forcibly evacuating all remaining patients and staff. The Israel Defense Forces said it detained 240 alleged militants, among them hospital director Dr. Hossam Abu Safiya. The IDF said the hospital was a “command center” for Hamas “military operations” in the surrounding area.

Ghebreyesus said Safiya’s “whereabouts are unknown. We call for his immediate release.”

Kamal Adwan patients were transferred to the Al-Shifa Hospital in Gaza City and the Indonesian Hospital in Beit Lahia, both of which have also reported repeated Israeli attacks. The latter “is itself out of function,” Ghebreyesus said.

“Seven patients along with 15 caregivers and health workers remain at the severely damaged Indonesian Hospital, which has no ability to provide care,” he added.

Four patients were detained by the IDF during their transfer out of Kamal Adwan Hospital, the WHO chief said.

Two other facilities — the Al-Ahli Hospital and Al-Wafa Rehabilitation Hospital in Gaza City — were also attacked and sustained damage on Monday, Ghebreyesus said.

“We repeat: stop attacks on hospitals,” he wrote. “People in Gaza need access to health care. Humanitarians need access to provide health aid. Ceasefire!”