How many years of prison is Mounir el - Motassadeq serving for the September 11 hijacking ?
Mounir El Motassadeq , a Moroccan living in Germany who belonged to the Hamburg cell apartment owned by Mohamed Atta and lived in by many other people who would later go on to lead the September 11 , 2001 attacks , in February 2003 was convicted in Germany of over 3,000 counts of accessory to murder in direct relation to the September 11 attacks , but the conviction was rejected on appeal .