The Plot Thickens

When Yussef Karroum drove his Chevrolet Celebrity station wagon across the border at Blaine, Wash., last Thursday at 9 a.m., he told Customs officials that he was entering the United States "to get gasoline, milk and cheese." Suspicious of the reply, Customs officers directed the 34-year-old Moroccan with a Canadian passport toward inspectors who punched his particulars into the immigration-service computer. First, law-enforcement officials say, the computer flashed a warning that Karroum should be considered "armed and dangerous." Investigators subsequently learned that Karroum's name was in the database because he was a suspected associate of Ahmed Ressam--the man arrested by Customs in December while trying to cross into Washington state with a cache of bomb-making materials.

Were terrorists launching another plot? Bomb-sniffing dogs (named Leon and Hilda) were brought to the car, as well as a device that can identify traces of explosives. The ma-chine identified nitroglycerin particles, law-enforcement officials say. None of that meant that Karroum had done anything illegal. He said he was an unemployed electrician, and he denied any knowledge of explosives in his car. The U.S. Attorney's office decided to hold Karroum only as a material witness; sources told NEWSWEEK that he was likely to be brought before a grand jury this week to be grilled about his knowledge of possible terrorist operations against the United States.

The Karroum case is just one of many that have investigators chasing new terrorism leads from the United States to the Middle East, Africa and Canada. Much of the fresh intelligence concerns the network of Osama bin Laden, the Saudi fugitive based in Afghanistan. Some of the 14 alleged bin Laden associates arrested in Jordan in December, for instance, have begun talking to investigators. U.S. law-enforcement officials say an attack on American and Israeli tourists over the New Year holiday was only narrowly averted. The planning of the attack, which was to be carried out at Jordanian holy sites, was "advanced and sophisticated," according to a secret FBI memo. Chillingly, the plotters were preparing to use "nonconventional explosive devices"--poison-gas bombs, say two knowledgeable U.S. sources. One of the alleged plotters was Khalil Deek, an Afghan-war veteran and U.S. citizen who had worked in California as a computer technician. A CD-ROM that police seized from his home contained bomb-building instructions, law-enforcement officials say. They describe Deek (who refuses to talk to Jordanian interrogators) as a key bin Laden lieutenant.

Counterterrorism officials apparently scored another coup in Jordan on Dec. 29, when police detained Khalil Ziyad, identified by the FBI as a Florida-based "procurement agent" for bin Laden. Jordanian security services did not publicly reveal the arrest, and later released Ziyad. But U.S. sources say he is cooperating with the FBI and providing crucial evidence about bin Laden's U.S. operations. Ziyad's role, according to an FBI memo, was to "procure computers, satellite telephones and covert surveillance equipment" for the leadership of bin Laden's organization.

The key link in the chain connecting bin Laden to Ahmed Ressam--and an alleged New Year's bomb plot in the United States--may be Mohambedou Ould Slahi. The Mauritanian was detained last week in Senegal, then released, and arrested again in his native country. Slahi had pre-viously been staying in Canada, where Ressam allegedly received the explosives he drove into Washington state on Dec. 14. (Ressam pleaded not guilty in federal court last week to charges of bomb smuggling and conspiracy to commit an act of terrorism.) U.S. and Canadian officials believe that Slahi is the brother-in-law of a key bin Laden aide, and that he acted as a liaison between bin Laden and a group of Algeri-an exiles that included Ressam. FBI agents hoped, at the least, to squeeze more fresh leads out of him.