Tens of thousands of pro-Palestinian demonstrators marched through a rainy London on Saturday to demand Israel stop its bombardment of Gaza, and similar calls were heard in cities around the world as the Israel-Hamas war entered its third week.

On the day a trickle of aid entered Gaza, where more than 1 million people have left their homes because of the conflict, protesters gathered in at Marble Arch near London's Hyde Park before marching to the government district, Whitehall.

Police estimated the crowd that wound its way through the city for three hours at “up to 100,000.”

Waving Palestinian flags and chanting “Stop bombing Gaza,” participants called for an end to Israel’s blockade and airstrikes launched in the wake of a brutal incursion into southern Israel by the Hamas militant group that controls Gaza.

Authorities in Gaza say more than 4,300 people have been killed in the territory since the latest war began. More than 1,400 people have been killed in Israel, mostly civilians slain during Hamas’ deadly incursion on Oct. 7.

Israel continued to bombard targets in Gaza on Saturday ahead of an expected ground offensive. A small measure of relief came when 20 trucks carrying humanitarian aid were allowed to enter Gaza across the southern Rafah border crossing with Egypt.

The war has raised tensions around the world, with both Jewish and Muslim communities feeling under threat. The British Transport Police force said it was investigating after footage was posted online that appears to show a London Underground driver leading passengers in a chant of “Free, free Palestine” over the subway intercom.

British authorities urged demonstrators to be mindful of the pain and anxiety felt by the Jewish community. London’s Metropolitan Police force says it has seen a 13-fold upsurge in reports of antisemitic offenses in October compared to last year. Reports of anti-Muslim crimes have more than doubled.

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Police said there had been "pockets of disorder and some instances of hate speech” during protests over the war, but “the majority of the protest activity has been lawful and has taken place without incident.”

Hundreds of pro-Palestinian protesters also gathered in Belfast and in Northern Ireland’s second city, Londonderry, where speakers included lawmaker Colum Eastwood of the Irish nationalist Social Democratic and Labour Party.

“The murder of children is wrong,” he told the crowd, calling for an immediate cease-fire in the conflict. “I don’t know how that is so difficult for some of our world leaders to actually utter. It doesn’t matter whether they are Israeli children or Palestinian children.”

Across the border in the Republic of Ireland, thousands marched through the capital, Dublin, calling for an end to Israel's bombardment.

In France, pro-Palestinians demonstrators gathered in several cities including Rennes, Montpellier, Dijon and Lyon, where thousands of people could be seen chanting “we all are Palestinians” in the central square.

In Marseille, the country’s second-largest city, some people took to the streets, waving Palestinians flags and shouting “Free Gaza,” despite the protest being banned by local police.

A pro-Palestinian gathering scheduled for Sunday in Paris has been allowed by police.

German police said almost 7,000 people took part in a peaceful pro-Palestinian demonstration in Düsseldorf on Saturday. The demonstrators carried Palestinian flags or banners calling for an end to “violence and aggression in Gaza.”

Police in Berlin banned a pro-Palestinian demonstration that was scheduled for Sunday in the center of the city, German news agency dpa reported. Police in the German capital have stopped several similar events in recent weeks, citing the potential of violence and antisemitic hate speech. Some pro-Palestinian demonstrators have taken to the streets anyway, resulting in clashes with police.

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Authorities allowed a pro-Israel demonstration scheduled for Sunday that was expected to draw together thousands of people in central Berlin.

Elsewhere, several hundred people marched through Rome on Saturday, some holding signs saying “Palestine, Rome is with you,” and “No peace until we get freedom.”

“Israel carries out war crimes there, crimes against humanity there, and the international community has never acted,” said Maya Issa, president of the Movement of Palestinian Students in Italy, which organized the demonstration.

Tens of thousands of demonstrators waving Palestinian flags flooded the streets of downtown Barcelona to demand an end to the Israeli airstrikes.

In Muslim-majority Kosovo, several hundred people walked from mosques to Pristina's Zahir Pajaziti square after lunchtime prayers to express support for Palestinians.

In Australia, thousands marched through central Sydney on Saturday, shouting “Shame, shame Israel” and “Palestine will never die.”

The war sparked protests across the Arab world and beyond on Friday, including in the occupied West Bank, where Palestinians burned tires and threw stones at Israeli military checkpoints. Israeli security forces responded firing tear gas and live rounds.

Crowds gathered in Israel’s northern neighbor Lebanon; in Iraq at the country’s border crossing with Jordan; in Jordan itself; in cities and towns across Egypt; in Turkey’s capital Ankara and its most populous city of Istanbul; and in Indonesia, Malaysia, Morocco and South Africa.

In New York, hundreds of protesters from Muslim, Jewish and other groups marched to U.S. Sen. Kristen Gillibrand’s Manhattan office, many shouting “cease fire now.” Police later arrested dozens of protesters who blocked Third Avenue outside Gillibrand’s office by sitting in the road.

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Thousands of demonstrators also marched through the streets of downtown Los Angeles demanding an immediate cease-fire.

Pro-Israel demonstrations and vigils have also been held around the world, many focused on securing the return of hostages captured by Hamas.

Rome’s Jewish community on Friday remembered the more than 200 people believed held by Hamas by setting a long Shabbat table for them outside the capital’s main synagogue and empty chairs for each of the hostages.

On the back of each chair was a flyer featuring the name, age and photo of each missing person. On the table were candles, wine and loaves of challah, the braided bread typically eaten during the Friday night meal.