Palestinian officials blamed an Israeli air strike for Tuesday's explosion in the besieged territory. Israel said the blast was caused by a failed rocket launch by the Palestinian Islamic Jihad militant group, which denied blame.
The bloodshed has enraged a region in crisis since Hamas, which controls the Gaza Strip, carried out a cross-border rampage against communities in southern Israel on Oct. 7 in which 1,400 people were killed and hostages were taken.
In Tunis, protesters burned Israeli and American flags and demanded the expulsion of the U.S. and French ambassadors for what they termed their unconditional support for Israel.
"They (Palestinians) have no food or water, and they are getting bombed. This is genocide, not war. This is a crime. We must find a solution," said Ines Laswed, a demonstrator.
Nadia Sweilam, a student, said: "The killing of hundreds of innocent people proves that we no longer have a choice but to resist. It's either them or us."
The death toll from the hospital explosion was by far the highest of any single incident in Gaza during the current violence, and saw protests erupt on Tuesday evening and again on Wednesday in the Israeli-occupied West Bank and the wider region, including in Jordan, Iran, Tunisia, Lebanon and Turkey.
In Amman, deployed riot police pushed back thousands of Jordanian protesters planning to march on the heavily fortified Israeli embassy.
"No Zionist embassy on Arab land," demonstrators chanted in the Rabia district of the Jordanian capital after noon prayers.
'REVENGE, REVENGE'
The protesters voiced slogans backing Hamas, including "Revenge ... revenge ... O Hamas, bomb Tel Aviv."
In Lebanon, security forces fired tear gas and water canon at protesters who were throwing projectiles as a protest near the U.S. embassy north of Beirut turned violent, footage broadcast by footage broadcast by Lebanese broadcaster al-Jadeed.
In Beirut's Hezbollah-controlled southern suburbs, thousands of people gathered for a protest, waving Hezbollah, Palestinian and Lebanese flags and chanting "Death to America".
"This entity (Israel), as we know very well, is built on the foundation of massacres," senior Hezbollah official Hesham Safieddine told the rally.
The French Foreign Ministry said on Wednesday it was advising its citizens against any travel to Lebanon, unless impossible otherwise, given the "security tensions in the region", especially at south Lebanon's border with Israel.
The move by France comes at a time of heightened security concerns across much of Europe linked to the Israel-Hamas conflict and to attacks by other Islamist groups such as Islamic State (IS). France says 24 of its citizens were among the 1,400 people killed in Hamas's Oct. 7 attack on Israel.
Eight French airports faced security alerts on Wednesday and several were evacuated for checks, and the Palace of Versailles closed again due to its third security scare in five days.
France is on its highest state of alert after the Oct. 13 murder of a schoolteacher in a suspected Islamist attack.
Italy on Tuesday arrested an Egyptian and an Italian citizen of Egyptian origin on suspicion of terrorism offences and being members of IS, the Milan prosecutors' office said.
Italy has also stepped up surveillance, especially in crowded areas, and increased protection for sites that might be targets for attacks, Interior Minister Matteo Piantedosi said, in light of the war between Hamas militants and Israel.
(Reporting by Tarek Amara in Tunis, Suleiman al-Khalidi in Amman, Tom Perry in Beirut and Benoit Van Overstraeten in Paris; editing by William Maclean and Mark Heinrich)
