An investigation into security at the Nuclear Regulatory Commission's national headquarters has determined that as many as "100 foreign nationals are working at the facility, and up to 35 may be visa violators or illegal aliens."

According to sources close to the review, investigators have discovered that one Chinese national was "writing sensitive computer code on NRC computers" even though his visa was in violation. Furthermore, sources said he had never had a background check.

Though NRC headquarters, located in suburban Maryland outside Washington, D.C., is now off limits to the Chinese national, sources said he continues to work for the agency from his nearby home.

Similar situations and concerns at the Justice Department prompted a sweeping new policy announcement recently entitled "Non-U.S. Citizens Prohibited From Department of Justice Information Technology Systems."

A copy obtained by Fox News says that without scrutiny and clearance, foreign nationals "shall not be authorized to access or assist in the development, operation, management, or maintenance of department information technology systems."

The Pentagon is creating a similar policy, expected to be issued within 60 days, and following the Defense Department inspector general's recent conclusion that when sensitive military information is compromised, 87 percent of the suspects are employees, consultants or subcontractors.

With the new policies in effect, the Drug Enforcement Administration, which falls within the Department of Justice's purview, is experiencing a wrinkle in the new security blanket. Foreign nationals are hired all the time to translate wiretapped calls between international smugglers. The translations often are done at military installations at home and abroad and sensitive government computers are used to dictate the messages.

The Immigration and Naturalization Service is supposed to assist with checking the backgrounds and monitoring these individuals but insiders say more often then not procedures and rules are just ignored.

Last week, INS Commissioner James Ziglar issued a new policy of zero tolerance for any deviation from established immigration policies and procedures after it was discovered that an INS inspector violated some of the agency's rules when he approved shore leave for four Pakistanis who then never returned to their ship in Norfolk, Va., and have been missing ever since.

Ziglar's zero tolerance policy drew immediate fire from critics who said it would tie law enforcement's hands and make their jobs tougher since so many INS rules are contradictory or create unnecessary bureaucracy.

To cut some of that bureaucracy, the commissioner has revised his zero tolerance plan to say INS agents should use their common sense and discretion when deciding if the rules should be applied.

After May 1, INS border patrol agents nationwide will also be relieved from requirements that they answer to the East, West and Southern regional offices, sources said. Instead, border patrol will be put directly under the authority of headquarters in Washington. Other INS law enforcement officers will still have to go through their various field and regional offices.

Critics say INS should cut all the red tape, and put all of law enforcement under headquarters' command, not just border patrol but so far that is not in the works.

Carl Cameron currently serves as Fox News Channel's (FNC) Washington-based chief political correspondent. He joined FNC in 1996 as a correspondent.