German authorities have charged three Iraqi men with membership in a terrorist organization on allegations they fought for the Islamic State group in their home country, including one suspected of attacks that killed American soldiers.

Federal prosecutors said Monday Mohammed Rafea Yassen Y., whose last name wasn't given for privacy reasons, joined IS in his hometown of Rutba.

The 28-year-old is accused of 13 bomb attacks in the city from 2006-2008, causing death and injuries to "U.S. forces, the Iraqi army, local police and civilians." He also faces war crimes and accessory to murder charges.

Muqatil Ahmed Osman A., 29, and Hasan Sabbar Khazaal K., 27, are both suspected of fighting for IS.

They came to Germany in 2015 and have been in custody since they were arrested last summer.