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. Bin Laden, a dissident Saudi businessman, has been indicted for the 1998 bombing of two U.S. embassies in East Africa and is believed to be responsible for last fall's bombing of the USS Cole in Yemen. Four alleged bin Laden associates went on trial Monday in federal court in New York for the embassy bombings. The testimony, at a closed-door hearing, was later made public. Citing security concerns, officials declined to name the sites.
Experts say it's difficult for law enforcement to intercept the messages.
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. Only the members of the terrorist organizations, knowing the hidden signals, are able to extract the information. Officials say bin Laden began using encryption five years ago, but recently increased its use after U.S. officials revealed they were tapping his satellite telephone calls in Afghanistan and tracking his activities. We have the best minds working with us.