The two brothers were said to have spoken about attacks that they wanted to commit at the fanzone on the Rogierplein in Brussels. Telephone conversations were intercepted by the security forces. The Louisalaan and several foreign embassies were also mentioned.
Their defence argued that they were the victims of a misunderstanding and wrongful interpretations. No arms or explosives were recovered during house searches. The brothers were detained on the night of 17 December when police raided 40 premises as well as 152 garages.