HAMBURG, GERMANY (REUTERS) - Mounir El Motassadeq, a friend of the September 11 hijackers who was sentenced to 15 years in a German prison in 2007 for being an accessory to mass murder, was deported to his native Morocco on Monday (Oct 15).

One of only two men ever convicted in relation to the militant attacks of Sept 11, 2001 is being deported from his German prison, but it's unclear if this means freedom for him.

El Motassadeq has served most of a 15-year sentence, the maximum sentence for being an accessory to mass murder. But German authorities have declined to say what happens to him next.

It's thought he'll be taken to his native Morocco. But again, what would happen after hasn't been revealed.

El Motassadeq was a member of a group radical Islamists in Hamburg who helped orchestrate the al Qaeda attacks on the Pentagon and World Trade Center.

During his trial in 2007 his lawyers argued that he knew nothing of the plot. But prosecutors said at the time that he played a central role by handling the finances of several members.