British Prime Minister Boris Johnson said on Wednesday the government would support the local Jewish community in any way it could after a spike in anti-Semitic incidents, including an attack on a rabbi, following the outbreak of hostilities in Gaza.
The Community Security Trust (CST), which advises Britain's estimated 280,000 Jews on security matters, said it had recorded 106 anti-Semitic incidents since May 8 compared to 19 in the 11 previous days, a fivefold increase.
Responding to a question in parliament from Keir Starmer, leader of the opposition Labour Party, Johnson said: "I share his horror at the outbreak of anti-Semitic incidents and the government has conveyed that message loud and clear to those who are responsible for enforcing the law against hate crime."
"As a country and as a society... we call this out at every stage. We will not let it take root, we will not allow it to grow and fester."
In one high-profile incident, a video posted on social media on Sunday showed a convoy of cars bearing Palestinian flags driving through a Jewish community in north London and broadcasting anti-Semitic messages and calls for the rape of Jewish women from a megaphone.
Phave since arrested four men on suspicion of racially aggravated public order offenses and they were later released on police bail pending further investigation.
Police have also arrested two men for a religiously aggravated assault on a rabbi in Chigwell, to the north of London. He needed hospital treatment for concussion after receiving a number of blows to the head.
The CST said there had been several incidents of individuals shouting "Free Palestine" at random Jewish people, daubing graffiti next door to a synagogue and emailing abuse to Jewish community leaders.
In another case, a man stopped Jewish schoolchildren in London and threatened to punch them if they did not say they supported Palestine.
"There is a particular problem of cars, either individually or in convoys, driving through Jewish neighborhoods, waving Palestinian flags and shouting slogans in a way that is clearly intended to intimidate local Jewish communities," the CST said.
"The level of anger and hate that is directed at Israel always spills over into anti-Semitism at times like this and yet the people stoking this anger, online and on the streets, never take responsibility for this particular consequence."
Israel said on Wednesday it was not setting a timeframe for an end to hostilities with Gaza as its military pounded the Palestinian enclave with airstrikes and Hamas militants unleashed new cross-border rocket attacks.