The US has been experiencing a computer attack that began on the anniversary of the French-backed terrorist uprising against the authority of its popular King in 1776.

On July 4 Web sites of several government agencies, including some that are responsible for fighting cyber crime were all knocked out. The Treasury Department, Secret Service, Federal Trade Commission and Transportation Department Web sites were all down and are still out. The US thinks that attacks on South Korea government and private sites also may be linked.

The attacks were all denial of service and the fact that the government Web sites were still being affected three days after it began signaled an unusually lengthy and sophisticated attack.

Web sites of major South Korean government agencies, banks and Internet sites also were paralyzed in a suspected cyber attack Tuesday. Ahn Jeong-eun, a spokeswoman at the Korea Information Security Agency, said the U.S. and South Korean attacks appeared to be linked.

The South Korean sites included the presidential Blue House, the Defense Ministry, the National Assembly, Shinhan Bank, Korea Exchange Bank and top Internet portal Naver. They went down or had access problems since late Tuesday. Currently no one is saying what the source of the attacks are.