The Japanese Government has suffered a spate of cyberattacks on two of its Web sites this week, according to reports.
A government spokesman told the Associated Press that key Web servers stopped working after hackers flooded them with data, making it impossible for people to access the Prime Minister's Office and the Cabinet Offices' Web sites.
Government IT staff saw three waves of attacks on Tuesday and Wednesday, but no permanent damage was caused, officials claimed.
Investigators are said to be unsure whether the source of the attacks is domestic or foreign.
In 2004, a Japanese Web site for the controversial Yasukuni shrine was taken offline five times following a string of denial-of-service attacks.