FBI Director Robert Mueller warned US lawmakers Wednesday that violent extremists could try to carry out cyberattacks on the United States and the nation needed to be prepared.
"To date, terrorists have not used the Internet to launch a full-scale cyber attack, but we cannot underestimate their intent," Mueller told a House appropriations subcommittee.
"They may seek to train their own recruits or hire outsiders, with an eye toward pursuing cyber attacks.
"As our nation's national security and criminal adversaries constantly adapt and evolve, so must the FBI be able to respond with new or revised strategies and operations to counter these threats," Mueller said, presenting the FBI's 2013 budget.
Al-Qaeda recruits and other extremists "are not hiding in the shadows of cyber space," Mueller added, pointing to the group's use of online chat rooms and websites to "recruit and radicalize followers to commit acts of terrorism."
He noted militants have shown interest in hacking skills, making "the FBI's counterterrorism mission that much more difficult and challenging."
He also highlighted that Al-Qaeda's lethal Yemen-based branch publishes an English-language online magazine, "Inspire," while Shebab militants linked to Al-Qaeda in Somalia use Twitter to "taunt its enemies -- in English -- and encourage terrorist activity."
The FBI has seen an 84 percent increase in the number of computer intrusion investigations opened, according to Mueller. The bureau also has cyber squads in each of its 56 field offices, as well as over 1,000 specially trained staff running undercover operations and examining digital evidence.
On Tuesday, US officials charged five alleged computer hackers in Britain, Ireland and the United States in high-profile cyberattacks after a leader of the group became an FBI informant.
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