Slahi's 2000 arrest and detention in Senegal turned what was meant to be a return home into the first stage of an extended cross-border detention. Arrested at Dakar airport alongside his brothers, he was questioned for several days about the Millennium Plot. Senegalese officials saw no reason to keep him, but American pressure shaped what happened next: instead of leaving freely, he was handed over to Mauritanian authorities and questioned again. The episode established the pattern that would define his subsequent journey—local custody, American interest, and a homecoming repeatedly deferred.

The journey to Dakar

After twelve years studying, living, and working abroad, mostly in Germany and briefly in Canada, Slahi decided to return to Mauritania. His trip began in Montreal on January 21, 2000, continued through Brussels, and ended in Dakar, where his brothers had come to meet him. He expected them to accompany him onward to Mauritania. The arrest therefore came at the point of reunion and transition, not after a flight from authorities: he travelled under his own name and passport and completed the formalities of an ordinary journey.

At the airport, Slahi had just collected his bag and turned toward the exit when agents seized him and put his hands in restraints. He initially thought the group was committing a robbery. He called out to his brothers, who were out of sight; only later did he learn that they, too, had been arrested, along with two of their friends. One friend had travelled from Nouakchott with the brothers, while the other, who lived in Dakar, had joined them for the airport trip. Senegalese authorities released the two friends, but kept Slahi and his brothers for questioning.

Questioning and the decision to transfer him

The questioning focused on the Millennium Plot, the alleged plan to bomb Los Angeles International Airport. The Senegalese interrogators were working from questions sent by American investigators. A senior Senegalese official took Slahi to his office and called the minister of internal affairs. Slahi could not hear the minister’s response, but heard the official say that Slahi was not the head of a terrorist organization and that he had no reason to keep him in jail. The official’s view contrasted with the substantial volume of material the United States had supplied about Slahi, which, in his account, did not persuade the Senegalese officials to detain him on its own merits.

The Senegalese authorities nevertheless understood that the United States would influence the outcome. Slahi’s brothers told him that Senegal was not interested in holding him, but that the United States would make the decisive call. His brothers eventually left, at the official’s suggestion, and Slahi remained in custody. Over the following days, interrogators returned to the same questions. Slahi later said that the Senegalese neither harmed nor threatened him. Because the jail’s food was poor, his brothers arranged for a family they knew in Dakar to bring him one meal each day.

The distinction between release and freedom became explicit when officials told Slahi they were releasing him, then immediately explained that they had to turn him over to his country. He first understood the announcement as a chance to choose where to go; the clarification ended that hope. The handover meant transfer to Mauritania, where authorities questioned him further about the same plot. A timeline in the book gives February 14 as the date of his release from the first detention, while its overview says he was released on February 19; both accounts place the end of the Senegalese episode in February 2000.

A first detention in a longer sequence

This arrest began the detention odyssey that Slahi describes as an approximately twenty-thousand-mile journey over eighteen months. Senegal was the first of four countries in which he would be held and questioned during that period, often with American participation and at the request of the United States. In Mauritania, officials eventually concluded there was no basis to believe he was involved in the Millennium Plot and released him. He returned to work and family life, but was detained and questioned again in September 2001, after the September 11 attacks. The later detention was a separate event; the Senegal arrest had not established his guilt, and the initial investigation remained focused on the alleged plot against Los Angeles International Airport.

The first episode also foreshadows how physical custody and the circulation of allegations could diverge. Senegalese officials questioned Slahi using American-supplied inquiries, but their own senior official said he had no reason to keep him. The detention ended not with an independent decision about his destination, but with a transfer to Mauritania. Later, the United States would move him through secret detention in Jordan and Bagram Air Base to Guantánamo. His family would for a time believe he remained in Mauritanian custody, unaware that he had been transferred abroad.

Later allegations and the meaning of the arrest

The case against Slahi changed over time. In 2000, the questioning in Senegal and Mauritania concerned the Millennium Plot. When he later appeared before a federal court in 2009, the United States did not argue that he was a major al-Qaeda figure or that he had participated in al-Qaeda attacks; its detention argument instead relied on alleged organizational membership, association, and assistance. The government also abandoned an earlier argument that he was detainable because he had aided the September 11 attacks, acknowledging that he probably did not even know about them. These later proceedings do not alter what happened in Dakar, but they make the limits of the original arrest consequential: the detention began with one investigative focus, while subsequent allegations and public descriptions expanded and shifted.

The Dakar episode is thus both a specific arrest and the opening of a larger system of transfers. Slahi arrived expecting a homeward journey with his brothers; he left Senegalese custody only to be delivered into another authority’s hands. The officials who questioned him in Senegal did not find a reason to keep him, yet their assessment did not restore his control over where he would go. That gap between an absence of grounds to hold him and the continuation of custody is the arrest’s decisive significance.