The indictment said the suspects, mostly Moroccans, had formed two terror cells in 2003 --one in Morocco and one in Madrid --and concluded that after Spain sent peacekeeping troops to Iraq that year, the country was "an enemy of Islam and therefore it was necessary to stage an attack" in Spain.
The 13 men were arrested in raids starting last October after police claimed to have foiled a planned suicide truck bombing to blow up the National Court, the hub of Spain's investigation of Muslim extremism, including last year's train bombings in Madrid.
However the indictment issued by Judge Fernando Grande-Marlaska did not specifically accuse them of planning to destroy the court. It only charged them with belonging to a terrorist group, namely al-Qaeda.
Mohamed Achraf, the jailed Algerian suspected of masterminding that plot, was not among those indicted Wednesday.
Four of the 13 men indicted are fugitives. Eight are in jail in Spain and one is in prison in Morocco in connection with the Casablanca bombings of May 2003.
The indictment said the Madrid cell also included two key suspects in the March 11, 2004, train bombings in Madrid --Moroccan Jamal Zougam and Egyptian Rabei Osman.
But the judge said he is not indicting them in this case because they are already under investigation over the train bombings, which killed 191 people. No indictments have yet been issued over that attack.
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