A Moroccan believed to have a long history of "intensive contacts" with the Sept. 11 hijackers was arrested by German authorities Wednesday.

The man had power of attorney over hijacker Marwan Al-Shehhi's Hamburg bank account, the prosecutor's office said.

The arrest of Mounir El Motassadeq, 27, at his home in Hamburg was the first in Germany directly related to the terror attacks. The country was used as a base of operation for many of the hijackers, including suspected ringleader Mohamed Atta.

The money in the account financed Al-Shehhi and other members of the terrorist group, including Atta and hijacker Ziad Jarrah, the prosecutor's office said in a statement. It also financed Al-Shehhi during his stay in the United States and was used to pay for his flight training at a school in Florida.

"Large sums of money" were regularly paid into the account from May 2000 to November 2000, the statement said.

"The accused maintained intensive contacts over several years" to the suicide hijackers, the prosecutor's office said.

A U.S. list of 370 individuals and organizations with suspected links to the Sept. 11 plot, posted on the Internet by Finnish financial authorities in October, lists a 27-year-old Mounir El Motassadeq of Morocco with a Hamburg address.

The Federal Prosecutor's Office identified the man arrested Wednesday only as Mounir El M., but a government official said on condition of anonymity that he was the same man as the one on the U.S. list.

It is common practice in Germany to withhold the last names of suspects.

El Motassadeq reportedly signed Atta's will, as did several Sept. 11 hijackers. When contacted in October, El Motassadeq angrily denied involvement in terrorism.

"All of this is false. I have nothing to do with this thing," he said before hanging up. El Motassadeq is believed to be married with a young child.

A woman who answered the phone at El Motassadeq's home Wednesday would not comment. Nobody would answer the doorbell to his second-floor apartment.

El Motassadeq has been a student at Hamburg's Technical University since 1995 — the same school where Atta, 33, and Al-Shehhi, 23, studied before leaving Germany last year for the United States.

He studied electrical engineering, according to school spokesman Ruediger Bendlin. Six days after the attacks, El Motassadeq was told police wanted to talk with him. Authorities interviewed him at the school, but he was not detained, Bendlin said.

In an October television interview that Bendlin sat in on, El Motassadeq said he had power of attorney on Al-Shehhi's account but had never made any transfers. He admitted knowing Atta and some of the other hijackers, and having visited the apartment where Atta, Al-Shehhi and others lived, Bendlin said.

Atta and Al-Shehhi were the suspected pilots of the hijacked airliners that crashed into the World Trade Center and Jarrah is suspected to have flown the plane that crashed in Pennsylvania.

Hamburg was also home to three other men believed to have helped plot the attacks. Ramsi Binalshibh of Yemen, Said Bahaji, a German national, and Zakariya Essabar of Morocco are all being sought on international arrest warrants.

Binalshibh is believed to have intended to be part of the team that hijacked United Airlines Flight 93, which crashed in southwestern Pennsylvania. He was denied a visa to enter the United States, despite three attempts by Atta to get him in, according to the FBI.

Bendlin said El Motassadeq admitted being at Bahaji's 1996 wedding at the al-Quds mosque in Hamburg. Atta, Al-Shehhi, Jarrah, and Essabar also attended the ceremony. El Motassadeq also told authorities he knew Binalshibh, and said he had signed Atta's will, as did others at the al-Quds mosque.

Mamoun Darkazanli, another Hamburg man who was on the U.S. list of potential suspects and whose business was named a terrorist organization by the United States, has told The Associated Press he was also at the wedding.

Darkazanli first caught the attention of German investigators in 1998 when they learned he had power of attorney over a German bank account opened by Usama bin Laden's suspected financial chief, Mamdouh Mahmud Salim, who was arrested that year.

Darkazanli denied any links to bin Laden, and said he only had access to Salim's account for a business deal that fell through.

Reached at his home after Wednesday's arrest, Darkazanli said he did not know El Motassadeq but could not say anything further on the advice of his attorney.

The Associated Press contributed to this report.