An online privacy group is suing the U.S. Department of Homeland Security accusing it of not releasing records from the agency's covert surveillance of Facebook, Twitter and other social media sites.
The DHS creates accounts solely to monitor social media sites and establish a system of records of the information gathered. The agency does not post information, seek to connect with other users, accept invitations to connect or interact with others according to a statement on their website.
The agency scans social media sites for a list of words that include "dirty bomb," "hostage," "exercise," "task force," "explosion," "lockdown," "riot," "nuclear threat," "brown out," "meth lab," "cain and abel" and "brute forcing."
Several countries and cities, including North Korea and Mexico, are also flagged as key words.
In a statement, the DHS said that the National Operations Center (NOC) "will gather, store, analyze, and disseminate relevant and appropriate de-identified information to federal, state, local, and foreign governments, and private sector partners authorized to receive situational awareness and a common operating picture," said the statement.
In April 2011, the Electronic Privacy Information Center (EPIC) requested records from the DHS of the agency's social network monitoring program. The agency has an obligation to locate the records and notify the requestor if the records are available for release.
Marc Rotenberg, EPIC's executive director, told ABC News that the requests have gone unanswered.
On Dec. 20, EPIC filed a Freedom of Information Act lawsuit against the DHS.
"We want to know how they're collecting information online, what they're collecting online and if there's legal basis to do this," Rotenberg told ABC News.
"We are trying to understand what the circumstances are when the DHS is engaged in tracking to social media sites," Rotenberg added.
The DHS declined to comment on the issue.
Former FBI agent and ABC News consultant Brad Garrett said this initiative is nothing new.
"One of the biggest overlooked areas of the federal government when it comes to crime and terrorism is diligently searching public source information," said Garrett.
Garrett said the DHS can see online information that's not available to the public as long as they have legal authority, in the form of a search warrant, to do so. But often people leave private information open to the public.
"People today are very open about their thoughts and feelings on a number of different topics. It amazes me the amount of information people will write about themselves online. There's a false security about the anonymity of sitting in front of a computer screen and saying things you wouldn't say in public or in front of your parents or your spouse," said Garrett.
Garrett said the DHS should be monitoring social media sites.
"It's one of those things that the government should be doing as long as they're obeying the law. I can't tell you how many bad guys have been caught because they do something bad and then post about it online," Garrett said.