Update Saturday, October 26 PM: The NSA site is finally back online. While there was no mention of the attack, the top story featured on the NSA site is, ironically, "General Alexander Statement Regarding Cybersecurity Awareness Month."

Original Report Follows:

The U.S. National Security Agency's website, nsa.gov, was knocked offline Friday afternoon, and as of Friday evening, it was still unavailable. Only a browser message indicating that the server was not responding appeared.

Sources quoted by various news agencies have speculated that the site has apparently fallen victim to a DDoS (distributed denial-of-service) attack, and that it was believed that the hacker group Anonymous would claim responsibility. However, as of the time of publication of this report, the group has not claimed responsibility.