The US Attorney's office in Brooklyn said that a federal grand jury had indicted Abdeladim El-Kebir, also known as "Abi al-Barra," with "conspiring to provide material support, including personnel, training, lethal substances and explosives, to al-Qaida."
"El-Kebir is also charged with conspiring to possess weapons, including a destructive device," the prosecutors' office said in a statement.
Details of the charges against El-Kebir, who was arrested in Düsseldorf this April, were not revealed. The Moroccan-born man was arrested with two others suspected of being al-Qaida members. The German Federal Prosecutor said at the time the group was experimenting with building a shrapnel bomb, with plans to detonate in a large crowd.
The American government is expected to request his extradition for trial.