Prosecutors alleged Friday that a Syrian-born doctor had blueprints for a suburban Washington overpass in his Brooklyn apartment and tried to help a suspected al Qaeda associate enter the United States.

But a federal magistrate denied the government's request to revoke the doctor's bail on an immigration charge after his attorney denounced the allegations as a smear based on old evidence and guilt by association.

The FBI's Joint Terrorism Task Force found the shredded blueprints for the Capital Beltway overpass at Connecticut Avenue in Hassan Faraj's apartment after he was arrested in June, prosecutors said.

Prosecutors also accused Faraj of submitting an affidavit saying he would financially support prospective immigrant Amir Abdulrazzak, whom they called a suspected al Qaeda associate.

They asked at a hearing Friday that Magistrate Judge Kiyo Matsumoto revoke Faraj's $100,000 bail.

Matsumoto did not jail Faraj, 39, but placed him under house arrest until a full hearing next week. Faraj's attorney, Stanley Cohen, said he plans to disprove each of the government's allegations.

Cohen said the blueprints, for example, belonged to Faraj's brother, a professor of civil engineering who had been teaching at a Washington area university. Faraj threw out the papers after the brother moved overseas, he said. Cohen declined to identify where the brother taught.

As for the alleged al Qaeda connection, "that accusation has no more significance than the rest of the government claims, which are based upon old, unproved and unconnected snippets of information," Cohen said.

Faraj was charged earlier this year with falsely obtaining U.S. citizenship after he arrived from Bosnia in 1993. Prosecutors said he lied to immigration authorities about his refugee status and medical experience. Prosecutors told the magistrate that Faraj worked in Croatia for a charity front organization that had ties to Osama bin Laden. Faraj's duties included running foreign recruits to camps in Bosnia, they said.