A German court on Friday opened hearings to set the sentence for a Moroccan friend of three of the Sept. 11, 2001, homicide pilots following his conviction as an accessory to murder in the attacks.

Judges could sentence Mounir el Motassadeq, 32, to 15 years in prison in the latest chapter of a tangled, five-year legal saga.

In November, a federal appeals court ruled that judges in Hamburg wrongly acquitted el Motassadeq in 2005 of direct involvement in the attacks, even as they sentenced him to seven years in prison for belonging to a terrorist group.

The appeals court convicted el Motassadeq as an accessory to the murder of 246 passengers and crew members aboard the aircraft used in the attacks, and ordered the Hamburg state court to set a new sentence.

The three-judge panel in Hamburg is expected to conclude the new hearings and announce a sentence by Feb. 5.

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Friday's hearing began with El Motassadeq's defense attorney Ladislav Anisic calling for the proceedings to be halted and his client released on procedural grounds.

El Motassadeq, 32, was a close friend of hijackers Mohamed Atta, Marwan al-Shehhi and Ziad Jarrah when they lived and studied in Hamburg. He entered the courtroom Friday looking relaxed and chatting to his interpreter.

The Moroccan has acknowledged training at an Al Qaeda camp in Afghanistan and that he was close to the three hijackers, but insists he knew nothing of their plans.

However, the federal court said evidence showed el Motassadeq knew that they planned to hijack and crash planes.

It found that his actions — for example, transferring money, and helping the hijackers keep up the appearance of being regular university students by paying tuition and rent fees — facilitated the attacks.

The federal court also said it was irrelevant to el Motassadeq's guilt whether he knew of the plot's timing, dimension or targets.

The sentencing hearings mark the third time that the Hamburg court has considered el Motassadeq's case. But it may not be the end of the saga that started with his arrest in November 2001 and has featured two full trials.

Lawyers for the Moroccan last month filed an appeal against his conviction with Germany's highest court, the Federal Constitutional Court. It is unclear when the court might consider the case.