Palestinian officials blamed an Israeli air strike for the huge blast and fireball which engulfed the Al-Ahli al-Arabi hospital. Israel denied responsibility and said the blast was caused by a failed rocket launch by the Palestinian Islamic Jihad militant group, which denied blame.

Biden's trip to the Middle East was supposed to calm the region, even as he demonstrated US support for its ally Israel, which has vowed to annihilate the Hamas movement whose fighters killed 1,300 Israelis in a rampage on Oct. 7.

But after the hospital blast, Jordan cancelled the crucial second half of Biden's itinerary: a planned summit in Amman with the leaders of Jordan, Egypt and the Palestinian Authority to shore up aid to Gaza and avert wider war.

The scenes of destruction from the hospital were horrific even by the standards of the past 12 days, which have confronted the world with relentless images, first of Israelis slaughtered in their homes and then of Palestinian families buried under rubble from Israel's retaliatory strikes.

Rescue workers scoured blood-stained debris for survivors. A Gaza civil defence chief gave a death toll of 300, while health ministry sources put it at 500. Palestinian ministry spokesperson Ashraf Al-Qudra said rescuers were still pulling bodies from the rubble.

No warning

Israel released drone footage of the scene of the hospital explosion, which it said showed it was not responsible because there was no impact crater from any missile or bomb.

The Israeli military also published what it said was an audio recording of "communication between terrorists talking about rockets misfiring".

But Palestinians were convinced the explosion was an Israeli attack, which they said came with no warning on a hospital that was being used as a shelter by thousands of Gazans already made homeless by Israeli bombing.

"This place created a safe haven for women and children, those who escaped the Israeli bombing came to this hospital," a doctor at the hospital, Ibrahim Al-Naqa, told Reuters.

He said hospital staff had been working normally on Tuesday evening and had received no warning when the explosion ripped through the building.

"We don't know what the shell is called but we saw the results of it when it targeted children and ripped their bodies into pieces."

Footage obtained by Reuters from inside the hospital in the aftermath showed around two dozen destroyed vehicles, many turned into mangled skeletons. Some vehicles nearby in the yard still had mattresses of displaced people on top of them.

Fury

The blast unleashed new fury on streets across the Middle East, even as Biden was desperately trying to calm emotions and prevent the conflict from sweeping across borders.

Palestinian security forces fired tear gas and stun grenades to disperse anti-government protesters in the West Bank city of Ramallah, seat of Palestinian Authority President Mahmoud Abbas, one of the Arab leaders who cancelled meeting Biden.

Protests also erupted at Israel's embassies in Turkey and Jordan and near the US embassy in Lebanon, where security forces fired tear gas toward demonstrators.

The US State Department issued a new warning to Americans not to travel to Lebanon, where border clashes between the Iran-backed Hezbollah movement and Israel over the past week have been the deadliest since the last all-out war in 2006.

Countries and international officials around the world denounced the blast, often with statements carefully worded to avoid saying who was to blame.

Biden has strongly backed Israel following the Oct. 7 attacks. But he is under intense pressure to win a clear Israeli commitment to alleviate the plight of civilians in the Gaza Strip, where 2.3 million Palestinians are under total siege, with no access to food, fuel, water or medical supplies.

The United Nations says half of Gaza's population has already been driven from their homes. Israel has ordered civilians to evacuate the entire northern half of the enclave, forcing families to cram into houses, schools and makeshift shelters in the southern half, even as it continues to pound the breadth of the enclave with air strikes.

The Israeli military announced on Wednesday that humanitarian aid would be made available in a "humanitarian zone" in Al-Mawasi on the south of the Gaza Strip coast near the Egyptian border. It did not spell out how aid would get there.

Hundreds of trucks carrying supplies have been backed up in Egypt at the city of Al-Arish, in hope that the Rafah crossing into Gaza would be opened, but talks have so far failed to let them in.

Egypt says the route is open on its side, but that Israeli bombardment of the Gaza side makes letting in aid impossible. Washington says the Israelis want systems in place to confirm that the aid will not benefit Hamas.

Speaking to reporters as Biden flew to Tel Aviv, White House national security spokesperson John Kirby said Biden would put "tough questions" to Israeli leaders, but did not give details.

"He'll be asking some tough questions, he'll be asking them as a friend, as a true friend of Israel, but he'll be asking some questions of them," Kirby said.

Popular

Magnitude 6.5 earthquake strikes off Java island: authorities

Philippines to endure extreme heat until mid-May

Indonesia one step from Olympics after beating South Korea