 In March 2004, Moumou was arrested in Copenhagen, Denmark, at the request of Moroccan authorities for his alleged role in the 2003 Casablanca bombings.He was released by the Danish authorities after a month and sent back to Sweden.While in Sweden, he was the "uncontested leader of an extremist group centered around the Brandbergen Mosque" in the Stockholm suburb of Haninge, according to the U.S. Treasury Department.