A spokesperson for the U.S. Marshals Service confirmed that it had disconnected from Justice Department computers as a precaution after being hit with the virus, while an FBI spokesperson would only say that it was experiencing similar issues, according to the report.
"We too are evaluating a network issue on our external, unclassified network that's affecting several government agencies," FBI spokesman Mike Kortan told the AP.
The virus' type and origin are unknown, but spokespeople for both agencies said agencies' access to the Internet and e-mail was shut down while the issue was evaluated.
Government regulations require agencies to report any security issues to US-Computer Emergency Readiness Team (US-CERT), but a call to CERT late Thursday for comment was not immediately returned.
This article was originally posed on CNET News.