A Moroccan accused of helping the Sept. 11 suicide pilots was a central member of an increasingly radical group around lead hijacker Mohamed Atta (search ) that believed "something had to be done against America," a witness testified Tuesday.

Shahid Nickels, a 23-year-old German student, was the first of more than 30 witnesses scheduled to appear before the Hamburg state court retrying Mounir el Motassadeq (search), who is charged with giving logistical aid to the Hamburg Al Qaeda (search) cell that included Atta and fellow hijackers Marwan al-Shehhi (search) and Ziad Jarrah (search ).

Nickels said he met the men in 1997 at Hamburg's radical al-Quds mosque, where he attended a Quran study class led by Atta.

The group believed that "Israel didn't have the right to statehood and suicide attacks were legitimate," Nickels said. "In America, they believed that the Jews had a lot of power."

The group's inner circle included el Motassadeq, Nickels testified.

The group became increasingly radical and by late 1999 the conversation "was all about jihad," or holy war, he said.

"They said that something had to be done against America — it was the general opinion," Nickels said.

Nickels then distanced himself from the group because, he testified, "I couldn't stand hearing any more about the guilt of the Jews."

Atta is believed to have been the pilot who crashed American Airlines Flight 11 (search ) into the World Trade Center's North Tower.

Al-Shehhi is believed to have been the pilot of United Airlines Flight 175 (search ) that crashed into the World Trade Center's South Tower.

Jarrah is believed to have been the pilot of United Airlines Flight 93 (search ) that crashed in a Pennsylvania field.

El Motassadeq, 30, was convicted in February 2003 of membership in a terrorist organization and more than 3,000 counts of accessory to murder and then sentenced to the maximum 15 years. Nickels testified during that trial.

But the conviction was overturned in March on appeal by a court that ruled he was unfairly denied evidence from U.S.-held Al Qaeda suspects including Ramzi Binalshibh (search ), believed to be the Hamburg cell's contact with the terror network.

After the retrial opened last week, the U.S. Justice Department sent the court summaries of the interrogations of Binalshibh and suspected Sept. 11 mastermind Khalid Shaikh Mohammed (search ). Both maintained that el Motassadeq was not part of the plot.

Binalshibh said the Hamburg cell comprised only himself and the three pilots, although the Justice Department cast doubt on the statements' credibility.

El Motassadeq is staying with his original defense: that he knew and was friends with most of the principals of the Hamburg cell, but he was not privy to their deadly plans.