in Chechnya, but were discovered by authorities and arrested. During the summer, two Hofstad group members traveled to Pakistan where they received paramilitary training. In September, the two men returned and it was discovered by authorities that these same men could be traced to having talked to a man having ties to the Casablanca bombings earlier that year. On 14 October of that year, the Spanish authorities arrested a Moroccan man who was suspected to be involved in suspicious activity. Police in the Netherlands arrested five Hofstad associates, including three who traveled abroad and were in contact with extremists in Morocco and Syria. In 2003, Mohammed Bouyeri, the man who murdered Dutch filmmaker Theo van Gogh, was radicalized. He withdrew from mainstream Dutch society by quitting his job and distancing himself from all friends and family who were non-religious. During this time, he became known as the "Taliban" by many in his neighborhood. In 2004, the group was under heavy surveillance by the AIVD, which dampened the group's activities. On 18 May 2004, authorities received a tip that a grocery store worker had been involved in preparing for a terror attack. A couple weeks later, the Dutch secret service had arrested this man after capturing him on security cameras taking measurements of the Dutch secret service headquarters. Upon his arrest, police found maps as well as weapons that could be used to carry out the terror attacks. On 29 August 2004, Van Gogh and Ayaan Hirsi Ali created a short film, Submission, that contained scenes of Quranic verses being painted onto semi-naked women. This was the catalyst for the group's radicalization and Bouyeri's justification to kill Van Gogh for the blasphemy of Islam. Claimed attacks Theo van Gogh's murder was the first terrorist attack claimed by the Hofstad group. In September 2004, authorities received a tip from an email that warned of two Hofstad group members preparing a terror attack. The anonymous source also admitted to being recruited by these men to carry out the planned terrorist attacks with particular targets. On 2 November of that year, Mohamed Bouyeri killed Van Gogh when he was on his way to work in Amsterdam. The killer cycled alongside the filmmaker before shooting him several times and attempting to decapitate him. Before fleeing the scene, he left a note pinned to Van Gogh's chest that had a death threat for Hirsi Ali. After