Documents obtained by FoxNews.com, which summarize these and other allegations and were given to congressional sources last week by a whistle-blower, described how a "secret grand jury" was to be convened in February 2011 to hear testimony from informants in the case, including a senior NASA engineer. But federal prosecutor Gary Fry was removed from the case, which was then transferred from one office in the Northern District of California to another where, according to the documents, "this case now appears to be stalled."

"The information is staggering," the whistle-blower told FoxNews.com.

The claims originate with several past and current NASA employees concerned with the systemic leak of highly sensitive information relating to missile defense systems, as well as what they call a troubled investigation into the leak.

The documents claim the FBI has been working with other agencies since 2009 on an investigation into foreign nationals working at Ames. This follows allegations by two Republican lawmakers earlier this month that the U.S. attorney's office in the Northern California district was ultimately denied by the Justice Department when it tried to proceed with indictments.

Melinda Haag, the U.S. attorney for the Northern District of California, denied claims her office was blocked in trying to proceed with the case.