"Followers of Wahhabism are changing Islam in our country and I believe that some local imams are not opposing them strongly enough," Esad Hecimovic, a Muslim journalist from Zenica, told AFP.

It was around this central Bosnian town with a Muslim majority population that the El-Mujaheed unit, serving with the country's Muslim-led army, dug in for the 1992-1995 war.

Hundreds of its members -- known as "holy warriors" or mujahedin -- who came from Islamic countries also converted Bosnian Muslims to Wahhabism, a hardline version of the religion that originated in 18th century Saudi Arabia.

"Since the war, the number of radicals has increased but they represent a frustrated minority due to their lack of power. However, they are very active and try to impose themselves," said Hecimovic, who is labelled by his detractors as an "enemy of Allah" because of his critical articles.

In the past few years, most Islamic humanitarian organisations preaching Wahhabism have gradually moved from Zenica to the capital Sarajevo, he said.

On a cold November day, hundreds of men gather for prayer in front of the striking King Fahd Mosque in Sarajevo, named after the late Saudi king who financed its construction.

Most are dressed in Western clothes, but about 100 Wahhabi community men are noticeable due to their short trousers and long beards, while some women wear the full chador, a scene which was hard to imagine in Bosnia before the war.

On stalls in front of the mosque the "bearded" sell different religious items, prayer beads and the Koran, but also video cassettes on the Chechen warlord Shamil Basayev during his war against Russian "infidels".

One can also buy "Saff," a bi-monthly publication founded by former members of the El-Mujaheed unit, which notably addresses Wahhabites. An editorial in its most recent issue criticises "American racism".

"They frighten me. A week ago a group of Wahhabites came to the mosque in my neighborhood and insulted believers accusing them of not being good Muslims," said Jasmin, a Muslim in his 20s.

"Also, among my former school colleagues some have stiffened their discourse and often use anti-Western rhetoric," he added.

Some 40 percent of Bosnia's 3.8 million inhabitants are Muslims. Serbs who are Orthodox represent about 31 percent, while Roman Catholic Croats account for around 10 percent.

Although after the war all foreign fighters were due to leave the country, an unspecified number of them remained and obtained Bosnian citizenship, mostly by marrying local women.

At the faculty of Islamic studies in Sarajevo, Professor Ahmed Alibasic rejects "concerns voiced by the press" and insists "Wahhabism is not a problem in Bosnia."

While acknowledging their influence on local Islam through Arab humanitarian organisations, Alibasic assures that Bosnia's Islamic Community, the leading religious Muslim body, "completely controls the situation".

"In Chechnya and Dagestan local Islamic authorities were weak and that is why 'foreigners' took over control," he stressed in a reference to conflicts in two of Russia's Caucasian republics in which Arab mujahedin take part.

"Extremists exist, of course, and it is necessary to fight against terrorism, but we should avoid generalising at any price," said Alibasic, for whom Bosnia's future lies within the European Union.

"The Islamic community rejects violence, extremism, intolerance, and an overwhelming majority of Bosnian Muslims follows this path," he said.