Hamburg, Germany ? A Moroccan student charged with aiding the Hamburg terrorist cell involved in the Sept. 11 attacks admitted Tuesday he trained in an Osama bin Laden camp in Afghanistan but denied knowing about the plot against the United States.

Mounir el Motassadeq, 28, is the first person to go on trial in connection with the suicide hijackings that killed thousands in New York, at the Pentagon and in a field in Pennsylvania.

El Motassadeq testified that he learned to fire a Kalashnikov assault rifle at the camp during three weeks of training in mid-2000 but was unaware it was run by bin Laden’s al-Qaida organization until he got there.

“I learned that bin Laden was responsible for the camp and had been at the camp sometimes,” he said. But, he added, “I didn’t know that beforehand and I didn’t meet him either.”

El Motassadeq, in custody since his arrest in Hamburg two months after the attacks, faces a possible life sentence if convicted of membership in a terrorist organization and more than 3,000 counts of accessory to murder.

His attorneys told the court he is innocent and denies prosecutors’ charges that he provided logistical support to the Hamburg cell, which included hijacker Mohamed Atta and two of the other pilots.

El Motassadeq said he met Atta at school in 1996 and that the two were friends, often eating together and discussing religion and politics. But, he said, Atta never told him about the Sept. 11 plot.

“I never expected Atta to do anything like this,” el Motassadeq said. “I still can’t believe he did it.”

El Motassadeq told the court he thought it was his religious duty to learn how to handle weapons. He said Atta recommended going to the camp after Atta returned to Hamburg from training in Afghanistan in May, 2000. El Motassadeq said he last saw Atta at that time.

“In Islam, it is wished that one learns to shoot,” el Motassadeq said, adding that he did not take explosives training in the camp, although it was offered.

When el Motassadeq was charged, Germany’s chief federal prosecutor, Kay Nehm, said the hijackers knew by October 1999 they would attack the United States with airplanes, but the idea likely originated elsewhere in the al-Qaida network.

In court, his attorneys argued the trip “proves nothing,” saying that thousands went to such camps without necessarily becoming terrorists.