A new report by the Policy Exchange claims mosques are being used to distribute extremist material.

The report entitled 'The Hijacking of British Islam: How extremist literature is subverting Britain's mosques,' reveals the extent of extremist penetration of mosques and other key institutions of the British Muslim community.

The report is the most comprehensive academic survey of its kind ever produced in the UK and is based on a year-long investigation by several teams of specialist researchers into the availability of extremist literature and covers more than a hundred mosques and Islamic centres throughout the UK.

The reports says most of the extremist literature is published and distributed by agencies linked to the Saudi Arabian government.

And that some of the most high-profile and prestigious mosques in Britain are among the worst offenders; in many of them, it is openly available.

Pamphlets, books and leaflets obtained from mosques and Islamic centres contain an assortment of shocking statements including: "Jihad against a tyrant, oppressors, people of bid'ah Muslim innovators, or wrongdoers. This type of jihad is best done through force if possible."

"The Jews and the Christians are the enemies of the Muslim."

"Whoever changes his religion, kill him."

Although some of the literature is in English, a proportion is written in Arabic. The translations commissioned by Policy Exchange have been independently verified.

Many of the publications encourage British Muslims to segregate themselves from non-Muslims. So-called unbelievers are to be treated as second-class and avoided wherever possible.

There are also repeated calls for gays to be thrown from mountains and tall buildings and for women to be subjugated.

Among the literature available are extracts from the notorious anti-Semitic forgery, The Protocols of the Learned Elders of Zion (published by the Saudi Ministry of Education), and other publications peddling bizarre conspiracy theories alleging that birth control is a plot against Muslims and Arabs, and that pornography is spread as part of a Jewish plot to corrupt Muslims.

Speaking about the findings of the report, Anthony Browne, Director of Policy Exchange said, "It is clearly intolerable that hate literature is peddled at some British mosques. I am sure the majority of moderate Muslims will be as horrified as everyone else that pamphlets advocating jihad by force, hatred for insufficiently observant Muslims, Christians and Jews, and segregation have found their way into the UK's mosques."

Mr Browne added, "The fact that the Saudi regime is producing extremist propaganda and targeting it at British Muslims must also be challenged by our own government.

"It is reassuring that the majority of mosques investigated do not propagate hate literature - but much work needs to be done to ensure that a large number of leading Islamic institutions remove this sectarianism from their midst."

The report calls for the Saudi Arabian government to be told to stop distributing extremist literature in Britain or else risk its good relations.

Mosques and other Islamic institutions must act immediately to remove extremist literature from their premises.

The government, local authorities, police forces, other institutions and prominent individuals should have nothing to do with mosques that continue to sell or distribute extremist literature.

Islamic schools must be subject to clear and rigorous regulation and made part of a genuinely shared system of national education.