By Craig Timberg and Ellen Nakashima, Published: December 6
The man who called himself “Mo” had dark hair, a foreign accent and — if the pictures he e-mailed to federal investigators could be believed — an Iranian military uniform. When he made a series of threats to detonate bombs at universities and airports across a wide swath of the United States last year, police had to scramble every time.
Mo remained elusive for months, communicating via e-mail, video chat and an Internet-based phone service without revealing his true identity or location, court documents show. So with no house to search or telephone to tap, investigators turned to a new kind of surveillance tool delivered over the Internet.
The FBI’s elite hacker team designed a piece of malicious software that was to be delivered secretly when Mo signed on to his Yahoo e-mail account, from any computer anywhere in the world, according to the documents. The goal of the software was to gather a range of information — Web sites he had visited and indicators of the location of the computer — that would allow investigators to find Mo and tie him to the bomb threats.
Such high-tech search tools, which the FBI calls “network investigative techniques,” have been used when authorities struggle to track suspects who are adept at covering their tracks online. The most powerful FBI surveillance software can covertly download files, photographs and stored e-mails, or even gather real-time images by activating cameras connected to computers, say court documents and people familiar with this technology.