Worldwide Internet traffic suddenly slowed down dramatically for hours on Saturday, after a fast-spreading computer worm clogged pipelines of the global network, officials said. Experts called it the most damaging attack on the Internet in 18 months as networks across Asia, Europe and America were effectively shut down. Even though the worst of the disruptions appeared to have passed by Saturday afternoon, some network disruption was likely to continue until Monday when businesses return to work, experts said. The explosive spread of the malicious program nearly cut off Internet providers in South Korea (news – web sites), disrupted automated bank teller machines in the United States and made online surfing, shopping and e-mail access difficult. The exact origin of the attack remained a mystery, and some experts warned that more destructive variants of the worm could appear soon. Full Story