United Nations Secretary-General Antonio Guterres is "deeply alarmed" at Sunday's strike by Israeli forces on the Al-Ahli Arab Hospital in Gaza, his spokesperson said on Tuesday.
"Under international humanitarian law, wounded and sick, medical personnel and medical facilities, including hospitals, must be respected and protected," the U.N. chief's spokesperson said.
He said the attack dealt "a severe blow to an already devastated healthcare system in the Strip", adding there was strong concern that medical supplies are running low as well as food and water.
Two Israeli missiles hit the major Gaza hospital on Sunday, putting the emergency department out of action and damaging other structures, medics said, in a strike that Israel said was aimed at Hamas fighters exploiting the facility.
Health officials at the Al-Ahli Arab Hospital evacuated patients after a phone call from someone who identified himself as Israeli security shortly before the attack.
No new humanitarian supplies have entered the Palestinian enclave since Israel blocked the entry of aid trucks on March 2, as talks stalled on the next stage of a now broken truce. Israel resumed its military assault on March 18.
Israel's Ministry of Foreign Affairs said 25,000 aid trucks had entered Gaza in the 42 days of the ceasefire and that Hamas had used the aid to rebuild its war machine, an allegation which the group has denied.

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