A sick chant calling for the murder of Jews was heard at an anti-Israel protest outside the U.S. Embassy, as community organisations unite in criticism.

Demonstrators at Friday’s rally, organised by groups such as the Palestine Solidarity Campaign, Socialist Workers Party, and Friends of Al Aqsa, the Stop The War Coalition among others, in response to Donald Trump recognising Jerusalem as Israel’s capital, were heard screaming “Khaybar Khaybar, ya yahud, Jaish Muhammad, sa yahud” – which translates as “Jews, remember Khaybar the army of Muhammad is returning”.

The chant references an infamous massacre of Jews in 628CE.

The protest, which was attended by up to 3,000 people according to organisers, saw marchers shouting slogans including “Down down USA” and “Hands off Jerusalem” , while the Campaign Against Antisemitism reported that on Sunday, “victory to the Intifada” was heard at a smaller protest at the same location.

The anti-Semitic chanting was condemned in a joint statement issued by organisers, who claim that “after the main demonstration had disbanded some of those who had been present remained and chanted slogans which demonstrated hatred and advocated violence.”

“We deplore such behaviours, which are not, shared or endorsed by our organisations or by the vast majority of those who attended the demonstration”, adding that they “stand against racism and discrimination of all forms including antisemitism.”

The Board of Deputies of British Jews, Community Security Trust and Jewish Leadership Council issued a joint response to the incident in a sign of communal unity, condemning the anti-Semitic chanting.

“The ‘Khybar, Khybar’ chant heard and documented at Friday’s protest outside the US Embassy in London can only be interpreted as a call to incite violence against Jewish people. It is outrageous that these protesters thought that such a chant would be acceptable on the streets of London in 2017. That this comes in the context of a firebombing of a synagogue in Sweden and an attack on a kosher restaurant in Amsterdam only increases our concern. These acts are not criticisms of a decision by the US government but demonstrations of anti-Semitism.”

“We welcome the condemnation by the protest organisers of this notorious Jihadi chant – which was clearly audible at the height of the demonstration – but urge them to take action to ensure that such acts do not go unchallenged at their events in the future. We further call on all of those who addressed the rally to unequivocally condemn the chants and undertake not to support or organise any event at which such activity is tolerated in the future.”

The police told Jewish News that the alleged anti-Semitic incident had not yet been reported, but that one person was arrested for a Public Order offence, unrelated to anti-Semitic chanting. In a statement, they said: “A 36-year-old man was arrested after a flare was thrown during a protest outside the US Embassy in Grosvenor Square on Friday, 8 December. The man was later issued with a Fixed Penalty Notice.No complaints have been received by the Metropolitan Police Service in relation to any other alleged offences during the protest.”

You can watch a clip of the incident featuring the alleged anti-Semitic incidents here: