Police investigating 'death to the IDF' chants allegedly led by Bobby Vylan on Al-Quds Day

LBC understands that a probe has been opened into the alleged chants led by Vylan, member of the band Bob Vylan, who attended the protest on Sunday.

The artist, real name Pascal Robinson-Foster, repeated his controversial Glastonbury chant - which Avon and Somerset Police took no further action over - while appearing as a speaker at the protest in London.

The remarks then appeared to prompt others in the crowd to join in.

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The Metropolitan Police said: "We are aware of chanting made by a speaker at the Al Quds protest and will be investigating.

"We recognise the concern footage and chanting like this causes, particularly with London’s Jewish communities.

"When this language had been used previously we sought advice from the CPS who determined that there would be insufficient evidence to take a case forward."

It comes as the Met also confirmed it had arrested 12 people during the protest and counter protest, which included participants showing support for a proscribed organisation and for using "threatening or abusive behaviour."

The arrests followed the Government's decision to allow the force to ban the the annual march, amid fears of serious disorder taking place because of its links to Iran.

But crowds were able to legally assemble and take part in a so-called "static protest."

Hundreds of people began arriving from 1pm, many holding Palestine flags and banners, some reading "Free Palestine" and "No to Israeli occupation."

The Al-Quds event takes its name from the Arabic version of the word Jerusalem, and was formed by Ayatollah Ruhollah Khomeini after Iran's 1979 revolution.

Pictures of Iran’s late leader Ayatollah Ali Khamenei were also held up, some accompanied by the message “Choose the right side of history”.

Chants of “from the river to the sea” and “Israel is a terror state” could be heard.

One protestor on the Al-Quds side of the protest told LBC: "I'm here to show support for Iran, the old Ayatollah and show support for the new one.

"They value humanity and they stand up for humanity. So it's important for me to stick with them where I can."

Another said: "He's the father of a nation. If you attack the leader, an 86-year-old man, surely it appears to be an act of war. I stand with the oppressed. And just as Ayatollah Khamenei said himself: "Stand with the oppressed".

A female counter-protestor told LBC: "I think it's great they come to help the Iranians in Iran bring a new regime which is help the people, not help the terrorism."

Around 1,000 officers were drafted in to police the action, which also included a counter protest in the city.

The Met's Assistant Commissioner Ade Adelekan, public order lead said: "Our policing plan worked, with both groups kept apart and we saw no attempts from either side to breach conditions by marching.

"Both sets dispersed as planned from 15:00hrs."We saw significantly fewer people attend than we had anticipated.

"The restrictions and conditions meant many people chose to stay away and not to attend the protest or counter-protest.

"This shows our decision to apply for the ban was the right one. A static protest meant it was easier for officers to keep the two groups apart and prevent serious public disorder.

"We made 12 arrests including for showing support for a proscribed organisation, affray and for threatening or abusive behaviour.

"We are also investigating chants made by a speaker at the Al Quds protest."

Earlier this week, Home Secretary Shabana Mahmood allowed the Met to ban the march, marking the first time a demonstration has been blocked in London since 2012.

Mr Adelekan added: "As I said from the outset, the decision to ban the protest march does not set a precedent and we will continue to consider each protest on a case-by-case basis.

"I want to extend my thanks to the officers, including those from across the country who supported us. Their professionalism and commitment helped us to keep protestors and Londoners safe."

A crowd of counter-protesters were seen on the opposite side of the Thames during a demonstration organised by Stop The Hate.

Police vans were parked along the road and on nearby Lambeth Bridge and police boats were seen on the River Thames.