By Dominic Casciani
Graffiti in north London since the start of latest Gaza conflict
Prominent British Muslims have denounced anti-Semitic attacks amid fears of a backlash against Jewish communities in Britain over Gaza.
The leaders said that British Jews "should not be held responsible" for Israel's actions in Gaza.
Jewish groups say there has been a record rise in anti-Semitic incidents since the crisis began.
A letter to mosques comes as muslim leaders urge ministers to do more to stop extremists recruiting young men.
In that letter, a broad range of scholars and progressive thinkers appeal to British Muslims to stand by British Jews, rather than allowing extremists to attack them.
The letter's signatories say they condemn "attacks on innocent British citizens and the desecration of places of worship".
"The ongoing killing of Palestinian civilians in Gaza by Israeli forces angered us all. However, this does not, and cannot, justify attacks on our fellow citizens of Jewish faith and background here in Britain.
"Most Muslims are completely against such behaviour," it continues. "British Jews should not be held responsible for the actions of the Israeli government."
The Community Security Trust, the main Jewish body that monitors anti-Semitism, says that there were 150 incidents in the 18 days since the conflict in Gaza began.
One synagogue suffered a suspected arson attack in north London. Most other incidents have involved verbal abuse, such as offensive phonecalls or shouts in the street. There has also been an increase in offensive graffiti.
The CST says half of incidents where the perpetrator is identifiable have been carried out by people described by the victim as either Muslim or Arab - higher than previously recorded.
The Metropolitan Police says it has recorded an increase in anti-Semitism in London.
Ed Husain, co-director of the Quilliam Foundation, explained what the letter said: "The gist of it is to say that over the last 1300 years we've seen relative peace and harmony between Jews in the Middle East, when there was disharmony here in Europe.
"No matter what British Muslims feel, and they rightly feel anger towards the Israeli government, nothing justifies attacking our fellow citizens of a Jewish background here in Britain."
Dave Rich of the CST said: "The incidents [since Gaza began] are far and away the highest number of incidents that we have recorded.
"The same 18-day period last year saw 24 incidents. During the war in Lebanon, we recorded 134 incidents in 34 days.
"The previous high was 105 incidents in October 2000 at the start of the second intifada."
Fears of extremism
Muslim community leaders met cabinet ministers for the second time in a week on Thursday amid fears that the conflict could derail government efforts to combat extremism.
The BBC understands that during the latest meeting, ministers were urged to do more to distance themselves from both Israel and US policy.
Many of the Muslims present said youngsters angry over the plight of Palestinians needed to hear clearer messages about British foreign policy, amid attempts by extremists to groom potential recruits.
Usama Hasan, an East London imam and community activist, said that he had seen a rise in extremist rhetoric, including new posters calling for violent jihad.
"The level of anger is so great over Gaza - nothing I have ever seen before, much higher than over Afghanistan," he said.