The Israel Defense Forces (IDF) military said early on Wednesday that its forces "are carrying out a precise and targeted operation against Hamas in a specified area in the Shifa Hospital, based on intelligence information and an operational necessity."
This follows several days of fighting at or near the hospital site, and conflicting claims about whether or not the facility is used by Hamas fighters.
The US on Tuesday had issued similar comments to Israel's, saying it had evidence of a Hamas "command and control node" at the Al-Shifa hospital site, where it believed weapons were also likely being stored.
Hospital officials and Hamas dispute these allegations and have complained of dire conditions at the hospital.
"The IDF forces include medical teams and Arabic speakers, who have undergone specified training to prepare for this complex and sensitive environment, with the intent that no harm is caused to the civilians being used by Hamas as human shields," the IDF wrote on social media.
The IDF said it had repeatedly warned privately and publicly that Hamas' alleged military use of the facility "jeapordizes its protected status under international law."
"Yesterday, the IDF conveyed to the relevant authorities in Gaza once again that all military activities within the hospital must cease within 12 hours. Unfortunately, they did not," Israel's military said.
Hamas says it holds Israel, Biden responsible for hospital raid
The Palestinian militant group Hamas accused both Israel and US President Joe Biden of responsibility for the apparent attack on the Al-Shifa hospital site.
"We hold the occupation [Israel] and President Biden wholly responsible for the assault on the Al-Shifa medical complex," Hamas said in a statement.
Hamas — recognized by the US, EU and others as a terrorist group — alleged that US government comments about the hospital being used for military purposes gave the "green light" to Israel to attack.
"The adoption by the White House and the Pentagon of [Israel's] false claim that the resistance is using the Al-Shifa medical complex for military ends has given the green light to the occupation to commit more massacres against civilians," Hamas said in a statement.
The White House had said late on Tuesday that it had intelligence suggesting Hamas was using the hospital. In the early hours of Wednesday morning, Israel's military said it had launched an operation at the site.
However, US officials, including the president, had simultaneously recommended restraint from Israel on Tuesday, with Biden urging Israel to take "less intrusive action" at the hospital.
Developments on Tuesday
US President Joe Biden hinted that he remained hopeful for a deal to release the hostages taken by Hamas in the October 7 attacks on Israel.
Families of the hostages began a five-day march from Tel Aviv to the residence of Israeli Prime Minister Benjamin Netanyahu in Jerusalem.
The White House said it had intelligence indicating that Hamas was using the Al-Shifa hospital site as a command and control node, seemingly supporting similar past claims by Israel.
German Chancellor Olaf Scholz criticized Turkey's President Recep Tayyip Erdogan, ahead of a meeting between the two on Friday, for Erdogan's sharp rebukes of Israel in recent days.
Heavy rains also hit Gaza on Tuesday, complicating matters further for people living in tents after fleeing Israeli bombardment. The tents offer little protection from the elements, and the rainfall could cause rapid build-ups of mud or potentially even overwhelm the sewage system.