Leaked diplomatic cables obtained by the WikiLeaks website and passed to The Daily Telegraph disclose fears that eastern Libya is being overrun by extremists’ intent on overthrowing Colonel Gaddafi's regime.

Former jihadi fighters who underwent "religious and ideological training" in Afghanistan, Lebanon and the West Bank in the 1980s have returned to eastern towns in Libya such as Benghazi and Derna to propagate their Islamist beliefs, the cables warn.

Derna has become a particular stronghold for the former fighters and conservative imams who have shut down "un-Islamic" social and cultural organizations such as sports leagues, theatres and youth clubs, the cables report.

Local sources blame deliberate government efforts to "keep the east poor" for growing extremism in towns such as Derna, according to telegraph.co.uk.

One cable sent to Washington in February 2008 reports a conversation with a local businessman who described the increasingly incendiary rhetoric at backstreet mosques in Derna, where coded talk of "martyrdom operations" had become commonplace.

The cable states: "By contrast with mosques in Tripoli and elsewhere in the country, where references to jihad are extremely rare, in Benghazi and Derna they are fairly frequent subjects."