Washington ? President Bush designated a Qatari man in U.S. custody as an enemy combatant Monday for an alleged role in helping al-Qaida operatives settle in the United States so they could mount new terror attacks.

The designation means that Ali Saleh Kahlah al-Marri, 37, could eventually be tried by a military tribunal without most of the legal rights afforded defendants in the U.S. criminal justice system, such as representation by an attorney.

Al-Marri, who lived in Peoria, Ill., has been in U.S. custody since December 2001. He was held first as a material witness and later charged with credit card fraud and lying to the FBI. Pentagon officials said al-Marri was transferred from federal civilian custody in Illinois to a Navy brig in Charleston, S.C.

Prosecutors say al-Marri had more than 1,000 credit card numbers in files on his laptop computer, which also contained oaths to protect al-Qaida leader Osama bin Laden, photos of the Sept. 11 attacks, files detailing weaponry and dangerous chemicals, and lists of militant Islamic Internet sites.

Alice Fisher, deputy assistant attorney general for the Justice Department’s criminal division, told reporters the decision to drop the charges and hand al-Marri over to the Defense Department was made not because the criminal case was weak but because it was the best way to deter future terrorist attacks.

“We are confident we would have prevailed on the criminal charges,” Fisher said. “However, setting the criminal charges aside is in the best interests of our national security.”

Al-Marri becomes the third person publicly designated by name as an enemy combatant since the Sept. 11, 2001, terrorist attacks.