Tens of thousands of people have taken part in a mass protest in central London to call for a permanent ceasefire in Gaza.
An estimated 45,000 protesters marched from Park Lane to Whitehall on Saturday carrying banners and placards, as police handed out leaflets that provided them with “absolute clarity” over what would land them in a cell.
A total of 18 people were arrested.
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Metropolitan Police said those arrested included four people who were handing out literature that featured a swastika inside a Star of David.
Another man was arrested on suspicion of inciting racial hatred as the demonstration began.
Two other people were arrested for wearing green headbands with white Arabic script – similar to those worn by Hamas, police said.
Shortly before 5pm, a “breakaway group” began to march up Whitehall. They were all detained for setting off flares, which had earlier also been directed at officers, police said.
Six people were arrested for refusing directions to disperse the area under Section 35 of the Public Order Act.
Ade Adelekan, Metropolitan Police deputy assistant commissioner, acknowledged the majority of people who “exercised their right to protest lawfully”, but added that a “small minority” believed the law did not apply to them.
The demonstrations came during a four-day break in fighting between Israel and Hamas.
Later in the day, Qatari and Egyptian mediators and the IDF said Hamas had released 13 Israelis and four Thai hostages in exchange for dozens of Palestinians imprisoned by Israel.
The release looked uncertain for several hours as Hamas delayed the process, saying Israel had violated the terms of the truce deal over the amount of aid reaching northern Gaza.
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Ahead of the weekend, the Met said more than 1,500 officers would be on duty, including 500 from outside of London, as part of a “robust intervention” to any criminal activity.
Mr Adelekan said ahead of the march: “Anyone who is racist or incites hatred against any group should expect to be arrested. As should anyone who supports Hamas or any other banned organisation.”
In Mayfair, hundreds of people gathered outside the Egyptian Embassy for a demonstration by the Islamic group Hizb-ut-Tahrir.
The crowd chanted “Muslim armies isn’t it time, Free Free Palestine,” according to a statement by the group, and men, women and children, held signs that read “Muslim Armies! Liberate Palestine!” and “US & UK Hands Off The Middle East”.
Two women were arrested at the 90-minute static protest on suspicion of racially aggravated public order offences over messaging on placards.
It was the group’s first protest since 21 October when a video that emerged of a man chanting “jihad” prompted backlash from politicians.
On Sunday, a 90-minnute march has been organised by charity Campaign Against Antisemitism, which is expected to be attended by around 40,000 to 50,000 people.