A picture is emerging of the shadowy figures suspected of being behind the 11 March Madrid bombings.
Fakhet is believed to have detonated the bomb in the flat
Of the six named on international arrest warrants, at least two died in an explosion at a flat in Madrid on Saturday as anti-terrorist police surrounded the building.
The supposed ringleader Serhane ben Abdelmajid Fakhet, 35, is reported to be the one who set off the bomb, destroying the besieged apartment, killing himself and four colleagues.
Another key figure, Jamal Ahmidan, 33, thought to be one of the cell commanders with links to al-Qaeda, also died in the blast.
Neighbours who lived near Fakhet, and many of the other suspects, had little reason to think that they were militants with a fundamentalist agenda.
Many of them appeared westernised and integrated into the Spanish community, with a liking for football, fashion, drinking and Spanish girlfriends, say Spanish press reports.
Neighbours said they were always polite, although sometimes hid their faces.
Fakhet, known as El Tunecino or The Tunisian, had been in Spain for eight years.
He had initially left Tunisia to study economics at Madrid University but later abandoned his studies.
Ahmidan, known as El Chino or Mowgli, was a westernised Moroccan
He had worked in Tetuan in Morocco buying and selling flats and was last known to have been living in a middle class suburb of Madrid.
Press reports say he lived with a 16-year-old Moroccan girl.
Unlike some of his more westernised colleagues, he is said to have been a religious fanatic whose beliefs had been recently radicalised, shunning Madrid's main mosques for their moderate stance.
The international arrest warrant names him as the "main dynamic element for raising the call for jihad, or holy war, among the people of his group".
El Mundo claims that police say Fakhet started to show "clear signs" of preparation for an attack in Madrid in 2003, influenced by communiques released by Osama Bin Laden's al-Qaeda network.
Investigating Judge Juan del Olmo believes Fakhet, using a false Belgian passport under the name Youssef Ben Salah, helped Ahmidan rent a farm in Morata de Tajuna near Madrid where the train bomb devices were prepared.
Little is known about Ahmidan, known as El Chino or Mowgli, except that his family owns clothes shops in the Lavapies area of Madrid.
El Pais quotes investigation sources as saying that Ahmidan had a key role in the 11 March attacks but did not actually plant any of the bombs.
Ahmidan is also said to have seemed happily integrated in Spanish society, whose Spanish friends are said to have included women who sported crop tops, tattoos and piercings.