Thousands of people rallied Saturday in central London for a pro-Palestinian protest following police warnings that anyone showing support for the militant group Hamas could face arrest.
Attendees, who gathered near BBC News' headquarters through the morning, began a march through the British capital ahead of an afternoon rally near parliament and Prime Minister Rishi Sunak's Downing Street office and residence.
Some displayed Palestinian flags and placards -- bearing slogans including "freedom for Palestine", "end the massacre" and "sanctions for Israel" as they made their way towards the end-point for a series of planned speeches.
"I think all just people around the world, not just in Britain, must stand up and call for this madness (to end)," Ismail Patel, chairman of the Friends of Al-Aqsa campaign, told AFP at the demonstration.
"Otherwise, in the next few days, (we) might see a catastrophe unfolding."
The rally comes as Israel intensifies its war to destroy Hamas' capability, relentlessly pounding the Gaza Strip and deploying tens of thousands of soldiers nearby ahead of an expected ground offensive in the enclave.
That follows last Saturday's attack by Hamas, which saw hundreds of its fighters cross the Israeli border to take hostages and kill more than 1,000 civilians on the streets, in their homes or at a rave party.
Ahead of the London protest, the city's Metropolitan Police Service said it would deploy more than 1,000 officers, as the events thousands of miles away reverberate in Britain and elsewhere.
In New York, cries of "Free Palestine" also rang out on Friday, as thousands of protesters took to the streets to denounce Israeli bombings in the Gaza Strip.
Calling for an end to "Israeli occupation" and the "liberation" of the Palestinian territories, protesters took up multiple blocks in a city that serves as a crossroads for religions and nationalities spanning the world.
The largely youthful protest -- which drew demonstrators of all origins, some sporting Palestinian flags and keffiyehs -- accused Israel of "genocide" and called for the US to withdraw support for its Middle Eastern ally.
Back in London, police and the UK government have noted a spike in UK anti-Semitic crime and incidents since the Hamas assault, while officers in Sussex, southeast England, arrested a 22-year-old woman Friday suspected of having made a speech backing Hamas.
A banned organisation in Britain, its members can be jailed for up to 14 years under UK law.
The Met said this week that general expressions of support for Palestinians, including flying the Palestinian flag, were not criminal offences but reiterated that supporting Hamas is a crime.
Ferouza Namaz, 34, a student from Uzbekistan, joined the London protest, arguing that civilians in Gaza are "absolutely innocent".
"Just being Palestinian does not give the right to kill them. These appalling atrocities have been taking place for so many years," he added.
Israel insists it does not deliberately target civilians in the Gaza Strip or other Palestinian territories.
But Ben Jamal, director of the Palestine Solidarity Campaign in Britain, told AFP its response to Hamas's attack was "dehumanising Palestinians" and unfairly blaming civilians for terrorism.
He attended the rally to send "a message of solidarity to the Palestinian people, and particularly today to the Palestinian people in Gaza, who are under bombardment, who are under siege with the cutting off of all food".
Jamal noted that those present were also conveying a message to UK political leaders, who he accused of "giving permission for Israel to commit acts of war crime".