Guido Rudolphi

Mohamedou Ould Slahi, who helped recruit three of the 9/11 hijackers and has been known to German and US intelligence for some time (see 1999), returns home to Mauritania in early 2000 and starts working at a series of internet cafes that appear to be cover for a radical militant communication network. Slahi is also thought to be involved in the Millennium Plot, is arrested and released twice before 9/11, and is questioned by the FBI and others about his knowledge of the Millennium Plot (see January-April 2000). After 9/11, Slahi will be investigated by an independent Swiss researcher called Guido Rudolphi, who runs an internet monitoring service. Rudolphi will find that Slahi runs a group of seemingly innocuous websites, but behind them there are guest books where visitors can leave messages. According to Rudolphi, this is the perfect communication tool for extremists, “[I]f you want to hide the content of the communication, you can put a message in the guest book. The owner of the guest book receives an e-mail, within seconds can look at the message, edit it, so it looks pretty normal, although the real content, which he has seen already, has disappeared, and may be harmful.” A dramatic increase in such traffic begins in May 2001, but then drops to an all-time low shortly before September 2001. By analysing the traffic, Rudolphi will find that the trail leads back to Duisburg, Germany, where Slahi studied at university. After 9/11, western intelligence agencies will come to the conclusion that Rudolphi’s research is well-founded and indicate that al-Qaeda had an operations center in Duisburg. [CNN, 3/6/2002]