FBI agents today executed more than 40 search warrants throughout the United States as part of an ongoing investigation into recent coordinated cyber attacks against major companies and organizations. Also today, the United Kingdom’s Metropolitan Police Service executed additional search warrants and arrested five people for their alleged role in the attacks.

These distributed denial of service attacks (DDoS) are facilitated by software tools designed to damage a computer network’s ability to function by flooding it with useless commands and information, thus denying service to legitimate users. A group calling itself “Anonymous” has claimed responsibility for the attacks, saying they conducted them in protest of the companies’ and organizations’ actions. The attacks were facilitated by the software tools the group makes available for free download on the Internet. The victims included major U.S. companies across several industries.

The FBI also is reminding the public that facilitating or conducting a DDoS attack is illegal, punishable by up to 10 years in prison, as well as exposing participants to significant civil liability.

The FBI is working closely with its international law enforcement partners and others to mitigate these threats. Authorities in the Netherlands, Germany, and France have also taken their own investigative and enforcement actions. The National Cyber-Forensics and Training Alliance (NCFTA) also is providing assistance. The NCFTA is a public-private partnership that works to identify, mitigate, and neutralize cyber crime. The NCFTA has advised that software from any untrustworthy source represents a potential threat and should be removed. Major Internet security (anti-virus) software providers have instituted updates so they will detect the so-called “Low Orbit Ion Canon” tools used in these attacks.