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Gallery: Terror in Madrid
MADRID, Spain (CNN) -- Spanish authorities are continuing to quiz three Moroccan suspects who they hope will lead them to those responsible for bombing Spanish commuter trains last week, killing 201 people.
Meanwhile the judge investigating the attacks ordered that an Algerian man detained for making terrorist threats be held another 48 hours while more information is gathered from police, a judicial official said Wednesday.
He said Ali Amrous, who met with Judge Balthazar Garzon for about hour in a private session, was being held in Madrid on suspicion of belonging to the al Qaeda terrorist group.
Authorities said the search for several others thought to be directly involved in the attacks is making progress.
Investigators suspect a militant Moroccan group linked to al Qaeda was behind the bombings, El Pais newspaper reported Wednesday.
El Pais said police believed those who carried out the attack were linked to the Moroccan Islamic Combatant Group, which it said is financed by al Qaeda.
The United States added the militant Islamist organization last April to its list of "terrorist groups." It said it emerged in the late 1990s and had members trained in Afghanistan.
Other reports quoted by Reuters news agency said the attacks on four commuter trains were meticulously planned over a period of up to 20 days and that police were hunting for 20 Moroccans, who may also be linked to the Casablanca bombings of last year.
Six arrests have been made so far, the latest Amrous on Tuesday. He had told police in January that an attack in central Madrid was planned.
El Mundo newspaper, quoting police sources, said 20 Moroccan citizens were being hunted in connection with the Madrid attacks. It said the same people were also suspected by Morocco of having participated in bombings in Casablanca last May which killed 45 people, including 12 suicide bombers.
The Madrid bombers spent 15 to 20 days studying train timetables and the stations, the Spanish newspaper La Vanguardia reported. It said two groups of three bombers each placed the explosives that ripped apart four trains.
The new reports came as Spain's prime minister-elect Jose Luis Rodriguez Zapatero rejected an appeal from U.S. President George W. Bush to stand by the U.S. and said his threat to withdraw Spanish troops from Iraq still stood. (Full story)
Meanwhile France, Britain and South Korea said they were potential targets for Islamic militants.
One of the three detained Moroccans has been identified as Jamal Zougam. The others are his half-brother and another Moroccan who together ran a mobile telephone shop in the capital, Reuters reported. Two Indians were also detained.
CNN's Alessio Vinci says that Zougam, 30, had been placed at the scene by two witnesses who reviewed police photographs.
Zougam has been linked to two men charged over the suicide attacks in Casablanca, authorities say.
That bombing has been tied to al Qaeda.
Zougam is also believed to be a follower of Imad Eddin Barakat Yarkas, the alleged ringleader of al Qaeda in Spain, according to a Spanish court document.
Spanish newspaper ABC reported Wednesday that Zougan had bragged to neighbors about belonging to an active Islamic militant cell.
"(Zougam) used to meet (in the mosque) to practice martial arts and to listen to tapes calling them to the Jihad (holy war," a neighbor was quoted in the story as saying.
The Spanish government initially zeroed in on Basque separatist group ETA -- listed as a terrorist organization by the United States and European Union -- as the prime suspect.
Amrous, the man appearing in court Wednesday, was detained in northern Spain by Basque police.
Police said Amrous was involved in a disturbance in January in San Sebastian, telling police: "There are going to be some deaths on the Castellana, on the Plaza Castilla and in Atocha."
The Castellana is a major north-south thoroughfare in Madrid, the Plaza Castilla is a major intersection on that route and Atocha is the name of the station hardest hit in the bombings.
Thousands of Spaniards attended a special mass Tuesday evening in Madrid's Almundena cathedral to remember the bombing victims.
Queen Sophia and international diplomats joined the mourners, as the city's archbishop said the attacks plunged everyone into deep pain.