From the earliest days of the investigation, one of the mysteries about the Trade Center case was who drove the van packed with 1,200 pounds of volatile homemade explosives. Hapless Mohammed Salameh, who rented the Ryder van, had a penchant for fender benders that could have blown the van, the conspiracy and him to smithereens long before he ever reached the Trade Center. Now, according to a previously sealed indictment, Najem is named as the man who drove the bomb into the Trade Center’s underground parking lot.

Najem reportedly studied English in Wichita, Kans., and worked in a Dallas grocery store before hooking up in New Jersey with his old friend Ramzi Yousef, the alleged mastermind of the bombing. But Najem’s ties to any other conspirators remain vague. As the Yousef connections grow stronger, those to the Egyptian fundamentalist Omar Abdel-Rahman- on trial in a related conspiracy-may well be weakened. Yousef had no apparent ties to Abdel-Rahman’s flock. Even as they nab the chauffeur, the Feds may be losing their grip on the sheik.