ALEXANDRIA, Va. (AP) – A federal jury rejected the death penalty for al-Qaida conspirator Zacarias Moussaoui on Wednesday and decided he must spend life in prison for his role in the deadliest terrorist attack in U.S. history.

After seven days of deliberation, the nine men and three women rebuffed the government’s appeal for death for the only person charged in this country in the four suicide jetliner hijackings that killed nearly 3,000 people on Sept. 11, 2001.

The verdict came after four years of legal maneuvering and a six-week trial that put jurors on an emotional roller coaster and gave the 37-year-old Frenchman of Moroccan descent a platform to taunt Americans. The judge was to hand down the life sentence Thursday morning, bound by the jury’s verdict.

The jury did not reach the unanimity required for a death sentence. Whether jurors were split on that question or unanimous on a life sentence was not announced.

The jury did agree unanimously that Moussaoui “knowingly created a grave risk of death” for more than the intended victims of Sept. 11 and committed his acts with “substantial planning” _ accepting two of the aggravating factors necessary for a death sentence.

But they did not give sufficient weight to those findings to reach a death sentence, balancing them against mitigating factors offered by the defense. Jurors did not, however, accept defense arguments that Moussaoui was mentally ill.