Police estimated around 100,000 demonstrators gathered in the capital, as other rallies have been organised elsewhere in the UK including Manchester and Glasgow.

A suspect was arrested on Whitehall after an officer was assaulted and needed to go to hospital, the Metropolitan Police said, while a man allegedly heard shouting racist remarks was held on suspicion of a racially aggravated public order offence and making threats to kill.

Section 60 and Section 60AA orders have been put in place along the protest route, which allow officers to stop and search people without reasonable suspicion, and give them powers to require the removal of items such as face coverings which are concealing someone's identity.

Protesters young and old marched from Embankment and across Westminster Bridge waving Palestine flags and holding various placards, some saying "free Palestine", "stop bombing Gaza" and "end Israeli apartheid".

"From the river to the sea, Palestine will be free", was one of the chants heard from the crowds - despite controversy surrounding the slogan.

For some, it is a call to end the Israeli occupation of the West Bank. To others, including many Jewish groups, it is an antisemitic slogan - calling for a state extending from the Jordan River to the Mediterranean Sea, which would wipe Israel off the map.

Home Secretary Suella Braverman said the chant was antisemitic, claiming it is "widely understood" to call for the destruction of Israel.

A police horse knocked over a woman during the protest after it was startled by fireworks near the Houses of Parliament. She appeared to be fine when helped back up.

The route of the demonstration traverses Waterloo Bridge, the Strand, Whitehall and Parliament Street.

Ahead of today's event, the Metropolitan Police said there was no place for hate crime.

They said they would have 2,000 officers on duty across the city, adding that interventions are expected if protesters are heard to use the word "jihad" - a word with numerous interpretations including struggle or effort but also holy war.

They decided not to arrest a man filmed chanting words including "jihad" at a pro-Palestine protest last weekend after assessing the video and failing to identify any offences, with specialist Crown Prosecution Service lawyers reaching the same conclusion.

Authorities have also imposed a separate condition which prevents protesters gathering outside the Israeli Embassy in South Kensington.

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Meanwhile police are looking for three women and a man who attended pro-Palestinian protests in London - three of which had images on them of paragliders.

Paragliders were used by Hamas militants during their deadly surprise attack on Israel earlier this month.

Hundreds of Israelis were killed, including 260 people at a music festival.

Thousands of Palestinians have been killed in retaliatory strikes by Israel.