A U.K. investigation has revealed a significant link between Islamic terrorist groups and cyber crime, and experts say security officials must do more to understand and confront cyber crime as part of any overall strategy for combatting terrorism. Investigators in the United States and Britain say a trio used computer viruses and stolen credit card accounts to set up a network of communication forums and Web sites that hosted everything from tutorials on computer hacking and bomb-making to videos of beheadings and suicide bombing attacks in Iraq.