The FBI's Web site was taken offline by a denial of service (DoS) attack for several hours on Tuesday, UPI reports. The attack interrupted an online announcement of the 50th anniversary of the Bureau's "Ten Most Wanted Fugitives" list, a standard feature in Post Offices throughout America, which was celebrated Tuesday at FBI headquarters in Washington. A DoS attack overwhelms a Web site with anonymous requests for information. If the attack is robust enough, the server will crash as system resources are progressively tied up trying to answer the requests. There is no indication yet of whether Tuesday's attack was a distributed denial of service (DDoS) attack, such as those launched against high-profile commercial sites early last month, and which Bureau investigators have yet to solve. A distributed attack requires tools to be uploaded surreptitiously into unprotected client machines from which the attack is launched. The FBI continues to search for suspects in February's spate of DDoS attacks. The search has led US authorities to Canada, to seek assistance from the Royal Canadian Mounted Police. There was no immediate indication Wednesday whether the attack on the FBI site was connected to any suspects wanted in the DDoS attacks. ®