In the first days after the terror attacks on New York and Washington, Saudi Arabia supervised the urgent evacuation of 24 members of Osama bin Laden's extended family from the United States, fearing that they might be subjected to violence. Most of Mr. bin Laden's relatives were attending high school and college. They are among the 4,000 Saudi students in the United States. King Fahd, the ailing Saudi ruler, sent an urgent message to his embassy here saying there were bin Laden children all over America" and ordered, "Take measures to protect the innocents," the ambassador said. The young members of the bin Laden clan were driven or flown under F.B.I. supervision to a secret assembly point in Texas and then to Washington from where they left the country on a private charter plane when airports reopened three days after the attacks. A majority of the men who hijacked four airliners in the attacks carried Saudi passports. Surprisingly, Osama bin Laden was not a stranger even to a royal family member like Prince Bandar. In the early 1980's, bin Laden came to greet the prince and thank him for helping to build the coalition that fought against the Soviet occupation in Afghanistan. Mr. bin Laden is one of 52 children of a Yemeni-born migrant who made a vast fortune building roads and palaces in Saudi Arabia.