American media works ceaselessly to reveal details of our secret wartime plans to the world, but they’re completely uninterested in conducting investigations like this: Revealed: preachers’ messages of hate.

An undercover investigation has revealed disturbing evidence of Islamic extremism at a number of Britain’s leading mosques and Muslim institutions, including an organisation praised by the Prime Minister.

Secret video footage reveals Muslim preachers exhorting followers to prepare for jihad, to hit girls for not wearing the hijab, and to create a ‘state within a state’. Many of the preachers are linked to the Wahhabi strain of Islam practised in Saudi Arabia, which funds a number of Britain’s leading Islamic institutions.

A forthcoming Channel 4 Dispatches programme paints an alarming picture of how preachers in some of Britain’s most moderate mosques are urging followers to reject British laws in favour of those of Islam. Leaders of the mosques have expressed concern at the preachers’ activities, saying they were unaware such views were being disseminated.

At the Sparkbrook mosque, run by UK Islamic Mission (UKIM), an organisation that maintains 45 mosques in Britain and which Tony Blair has said ‘is extremely valued by the government for its multi-faith and multicultural activities’, a preacher is captured on film praising the Taliban. In response to the news that a British Muslim solider was killed fighting the Taliban, the speaker declares: ‘The hero of Islam is the one who separated his head from his shoulders.’

Another speaker says Muslims cannot accept the rule of non-Muslims. ‘You cannot accept the rule of the kaffir [non-Muslim],’ a preacher, Dr Ijaz Mian, tells a meeting held within the mosque. ‘We have to rule ourselves and we have to rule the others.’