The man charged with the murder of a controversial Dutch artist last week has been linked to a fanatical Islamic sect whose members are said to include the al-Qaeda second-in-command, Ayman al-Zawahiri, and the Jordanian terrorist Abu Musab al-Zarqawi.
Islamic experts believe that the style and content of a five-page letter that was found pinned to Theo van Goghís body were close to those of al-Takfir wal Hijra, a radical group that has declared war on westerners.
Mr Van Gogh, who had angered many Muslims after releasing articles, books and films critical of Islam following the attacks of 11 September, was attacked near a park close to the centre of Amsterdam last Tuesday.
Police arrested a 26-year-old man with dual Dutch and Moroccan citizenship at the crime scene following an exchange of gunfire in which a police officer was wounded.
Dutch authorities have since detained a further seven suspects on charges of conspiring to murder Mr Van Gogh and threatening to kill several Dutch politicians.
Founded in Egypt in the 1970ís, al-Takfir wal Hijra has been responsible for several acts of violence, including the assassination of Egyptian president Anwar Sadat in 1981.
The sectís strict interpretation of Islam endorses the indiscriminate extermination of infidels and secular Muslims.
Both al-Zawahiri and al- Zarqawi, the man behind many of the spate of kidnappings and beheadings in Iraq, are thought to be members of the brutal sect.
The organisation – whose name translates as “excommunication and migration” – is active in most Arab nations and has carried out attacks on both Muslims and non-Muslims in Sudan, Morocco, Algeria and Lebanon.
But their views are known to be excessive even among Islamic extremists – four members even attempted to assassinate Osama bin Laden in 1995 while he was staying in Sudan. Its followers are so fanatical for a pure Islamic world that they have been known to undertake killing sprees in mosques to drive out “corrupt elements”.
Most worrying for westerners is the fact that the sect apparently allows its members to appear non-radical, and even non-Islamic, if the mission requires it.
Shockwaves have been reverberating around the Netherlands for days following the killing of Mr Van Gogh.
Messages – later left at the pavement shrine where Mr Van Goghís throat was slashed – were full of venom against radical Islam. “Enemies live among us,” read one missive in a bed of flowers, votive candles and crosses.
“The Muslims say theyíre scared,” said mourner Nicolette Toering. “No, weíre scared.”
Mr Van Gogh – a distant relative of the famous painter – often tested the boundaries of free expression by denouncing Muslims in the most graphic terms.
The film-makerís fans were as passionate as his detractors.
“He was trying to warn us about the dangers of radical Islam,” said Geert Plas, a teacher, as he visited the site where Mr Van Gogh was ambushed. “Now maybe weíll listen. “To me this is not just a small event. Itís part of the World Trade Centre and Madrid. We must see this.” The letter pinned to the victimís body also threatened death to Hirsi Ali, who has gone into hiding, and predicted the downfall of the “infidel enemies of Islam” in Europe, America and the Netherlands.
The memorials that piled up on the pavement often crossed the line from sympathy to seething recrimination.
“This is the true face of Islam,” said one message. A framed poem called Imam ends with a stanza: “If you want to improve the world, start with yourself and your faith.”