Police have placed in custody a 38-year-old colleague of the Trappes terror suspect, after investigators concluded that the man was more than just an ordinary workmate. The detention followed the attack in Trappes, in the Yvelines department, on 23 October. Officers from the anti-terrorism unit (Sdat) questioned the man in the hours after the attack, placing him under guard because prosecutors believed he had played a key role in understanding the suspect’s path. Investigators say the colleague was the only friend of the terror suspect and described himself as a “basic colleague”. In the conversations leading up to the killing, he told police that he had been aware that talking about the plan to someone would make it fail. During his custody, the colleague recounted his last exchanges with the terror suspect. He told investigators he did not perceive any preparation for the attack. His statements are now part of the ongoing investigation into the suspect’s derailed project. The colleague remained in police custody as investigators continued to build their case.