Attorney General Eric Holder has moved to block release of information related to a lawsuit filed by Southern California Muslims who contend that the FBI monitored them because of their religion.

In a court filing, Holder invoked state-secrets rules to try and  prevent information from being released about the target of a 2006 surveillance of a mosque, according to several news reports. The filing argues that disclosure of the target could hurt national security.

The American Civil Liberties Union of Southern California and the Los Angeles office of the Council on American-Islamic Relations sued the FBI last February over the surveillance episode.

Josh Gerstein reported ^[1] Holder’s invocation of state secrets Monday on Politico, quoting from Holder’s declaration in court.  Allan Lengel, writing ^[2] on his Tickle the Wire Blog, and the Associated Press have also reported on the issue.

“Disclosure of the reasons for and substance of a counterterrorism investigation—whether the initial predicate for opening an investigation, information gained during the investigation, or the status or results of the investigation—could reasonably be expected to cause harm to national security,” Holder wrote. “Such disclosures would reveal to subjects who are involved in or are planning to undertake terrorist activities what the FBI knows and does not know about their plans and the threat they pose to national security.”