''e-jihad''

Osama bin Laden and other Muslim extremists are posting encrypted, or scrambled, photographs and messages on popular Web sites and using them to plan terrorist activities against the United States and its allies, U.S. officials say. The officials say bin Laden and his associates are using the Internet to conduct what some are calling ''e-jihad,'' or holy war. Bin Laden, a dissident Saudi businessman, has been indicted for the bombing in 1998 of two U.S. embassies in East Africa and is believed to be behind the bombing of the USS Cole in Yemen on Oct. 12. Four alleged bin Laden associates went on trial Monday in New York for the embassy bombings. ''To a greater and greater degree, terrorist groups, including Hezbollah, Hamas and bin Laden's al Qaida group, are using computerized files, e-mail and encryption to support their operations,'' CIA Director George Tenet wrote last March to the Senate Foreign Relations Committee. The testimony, given at a closed-door hearing, was later made public. Officials and experts say the messages are scrambled using free encryption programs set up by groups that advocate privacy on the Internet. Those same programs also can hide maps and photographs in an existing image on selected Web sites. The e-mails and images can only be decrypted using a ''private key,'' or code, selected by the recipient. Through weeks of interviews with U.S. law-enforcement officials and experts, USA TODAY has learned details of how extremists hide maps and photographs of terrorist targets -- and post instructions for terrorist activities -- in sports chat rooms, on pornographic bulletin boards and other popular Web sites. The officials, who declined to name the sites, say it is extremely difficult to intercept the coded messages.