Beghal was arrested on 28 July 2001 in Dubai as he was attempting to travel back to Europe on a false French passport after visiting an al-Qaeda camp in Afghanistan. During interrogation, Beghal said that there was a plan to attack the U.S. Embassy in Paris and told investigators of terrorist cells in Rotterdam and Paris. He also said that
Abu Zubaydah, a close associate of Osama bin Laden, had ordered the attack. After being extradited from the United Arab Emirates to France on 1 October 2001, Beghal retracted his confession, saying that it had been extracted using torture. Surveillance of a suspected terrorist cell led by
Kamel Daoudi in
Corbeil-Essonnes near Paris started on 10 September. Following surveillance officers overhearing discussion of destroying evidence, French police moved in and arrested seven men on 21 September. Daoudi was not among the arrested, but he was shortly thereafter arrested in
Leicester and extradited from the United Kingdom to France on 29 September 2001. Dutch police started surveilling the Rotterdam cell in August. The four members of the cell were arrested on 13 September. Police became aware of a connection between the Rotterdam cell and one led by Trabelsi in Brussels. Trabelsi and a Belgian Moroccan were arrested in two different areas of the Brussels metropolitan area on 13 September in an operation coordinated with the arrests in the Netherlands on the same day. At Trabelsi's apartment, police found machine pistols, chemical formulas for bomb-making, detailed maps of the U.S. embassy in Paris, and a business suit. In a restaurant run by one of Trabelsi's associates, police found materials that could have been used to make a bomb capable of blowing up a building. ==Legal proceedings==