Antisemitic incidents in Britain are rising in the wake of Israel's operation in Gaza.
The Community Security Trust says 70 incidents have been reported since July 8.
In one instance, "demonstrators on a march through central London assaulted and verbally abused a Jewish woman who expressed her support for Israel as they walked past. Marchers surrounded her, called her a 'Jew Zionist' and stole her phone.
"Later the same afternoon, demonstrators from the same march verbally abused another Jewish woman who was with her two young children, telling them to 'burn in hell'."
At the same demonstration, protestors held placards that compared the situation in Gaza to the Holocaust and likened Israel to Hitler.
The Palestine Solidarity Campaign claimed that 15,000 people joined the march from Downing Street to the Israel Embassy.
The CST said: "This level of violence from pro-Palestinian protesters is a worrying development. A pro-Israel organisation in London also received a telephoned bomb threat."
Mark Gardner, director of communications at the CST, said: "These marches are in danger of inciting violence and intimidation. We have made the police forces aware of our specific concerns relating to PSC demonstrations."
"We are sending out emails to schools, shuls and Jewish organisations reminding them of safety protocols. We are determined to do all we can to allow Jewish life to continue as normal."
He commended the work of faith groups such as Tell Mama and the Muslim Council of Britain for their efforts to "restore calm."
In another incident, a rabbi walking in north London was verbally abused by a group of youths who shouted "free Palestine, f*** the Zionists, f*** the Jews" and "Allahu Akhbar".
In Belfast, a brick was thrown through a synagogue window and in Liverpool people shouted "baby murderers" at a local shul.
The CST has also received reports that a Jewish boy cycling in north London was attacked by a woman wearing a niqab who threw a stone at him, hitting him on the head.
Police have charged four youths in connection with an assault on a rabbi in Gateshead. The victim, in his 40s, was attacked as he left a Jewish study centre last Friday.
Qaiser Malik, 19, and Balawal Sultan, 18, both of Newcastle, and male youths aged 17 and 16 have been charged with racially aggravated common assault. They appeared at South Tyneside Magistrates' Court on Saturday.
Northumbria police are investigating a potentially racist tweet showing a picture of what was described as a Jewish primary school and the message: "This Jewish school in Gateshead was cheering when bombs hit Palestine."
There were angry scenes on Manchester city centre streets outside a cosmetics business selling Israeli products, forcing police to deploy a tactical aid unit. On Tuesday, 30 pro-Palestinian protesters blocked the Kedem cosmetics shop. A customer barged past a Palestinian being held in his way prompting an angry reaction from demonstrators. A larger repeat protest on Wednesday faced a pro-Israel counter-demonstration.
The organiser of the pro-Israel protest, Martine Vaizman, said the mood had been conciliatory. "We were able to enter into dialogue. We even held a minute's silence for all the dead on both sides. We wanted protesters to leave alone an innocent British business which happens to sell Israeli products."
An appeal by the Muslim Council for Britain not to allow the Gaza conflict to disrupt interfaith relations in the UK was welcomed by the Board of Deputies. In a statement posted on its website Dr Shuja Shafi, MCB secretary-general, urged Jews and Muslims to "remember the importance of civility and courtesy between each other".
Board vice-president Jonathan Arkush said it was "an important statement from the MCB and we recognise that it marks a significant change of tone." The Board has not had formal relations with the MCB for a number of years after a fallout from previous Gaza hostilities.