Officials in Belgium and France heralded Abdeslam's live capture as a rare opportunity to learn more about functioning terrorist networks in Europe - especially those with links to Isis (Islamic State), which claimed responsibility for the Paris attacks.
Last November, authorities quickly identified him as the principal planner of the complicated logistics behind the attacks, saying he rented the cars his fellow terrorists drove to Paris and arranged accommodations for them in apartments and hotels.
This is an image confirmed in extensive detail by investigation documents from French security services, obtained by the Washington Post. Those documents give added weight and plausibility to the allegation that Abdeslam was actively pursuing new acts of organised terror. In facts and figures, they paint a clearer picture of the active role investigators say he played in the November attacks.
On November 10, for instance, the documents show that Abdeslam rented the Volkswagen Polo later discovered near the Bataclan concert hall in Paris, where gunmen killed 89 people. As records also show, he paid €350 for the car at the Astral Rent-a-Car agency in the Etterbeek neighbourhood of Brussels, providing his Belgian residency card as identification and promising to return the vehicle one week later.
The documents also indicate that he made reservations for his fellow attackers in the Appart'City Hotel in Alfortville, near Paris's Orly Airport. His genetic profile matches one discovered in a black Renault Clio also used in the attacks, as well as another discovered in the Bobigny apartment that several attackers shared before November 14.
On the day of the attacks, a bystander at Stade de France, the sports stadium where suicide bombers blew themselves up, recalled seeing three individuals whispering in Arabic outside the entry. According to the documents, he later identified Ahmad al-Mohammad and Salah Abdeslam in photographs.
Two days before the attacks, Abdeslam was observed at a service station en route to Paris with Mohamed Abrini, another attacker. The day afterwards, he was stopped - but not detained - at Cambrai, near the Belgian border, in a grey Volkswagen Golf with Hamza Attou and Mohammed Amri.
At least according to these documents, there were few aspects of the attacks that did not bear traces of Abdeslam. He is now being held in a high-security prison in Bruges but will likely stand trial in France, whose Government issued an extradition request. Belgian authorities have two months to hand him over but have three if he appeals.
Mary told reporters that he intended to take legal action against a French prosecutor for breaching the confidentiality of an ongoing investigation. That prosecutor, François Molins, had said at a news conference on Sunday that Abdeslam revealed to Belgian investigators his apparent plans to detonate a suicide bomb. Mary did not respond to requests for further comment.
French authorities dispatched more troops to the nation's borders after Abdeslam's capture. The international police agency Interpol urged "extra vigilance" at the borders of all 190 of its member countries. "Anyone linked to Abdeslam will be concerned that their location could be revealed and attempt to run," Jürgen Stock, Interpol's Secretary General, said in a statement.
