NSA's top investigator will review claims that agency spied on Fox News host Tucker Carlson

The National Security Agency's top internal watchdog announced Tuesday that he would begin reviewing claims that agents working at the top intelligence agency unmasked Fox News host Tucker Carlson's identity.

What is the background?

Carlson raised the alarm in late June when he alleged the NSA was "spying" on him with the motive of removing him from his primetime platform.

Carlson explained that a "whistleblower within the U.S. government" contacted his show to "warn us that the NSA, the National Security Agency, is monitoring our electronic communications and is planning to leak them in an attempt to take this show off the air."

"The whistleblower, who is in a position to know, repeated back to us information about a story that we are working on that could have only come directly from my texts and emails," Carlson explained. "There's no other possible source for that information, period."

The Fox News host, however, did not provide evidence to substantiate his allegation, nor did he explain what information had been intercepted. Carlson emphasized the behavior he described was both unethical and illegal.

What did the NSA say?

NSA Inspector General Robert Storch announced Tuesday that his office is "conducting a review related to recent allegations that the NSA improperly targeted the communications of a member of the U.S. news media," a reference to Carlson.

The statement explained:

The [Office of Inspector General] is examining NSA's compliance with applicable legal authorities and Agency policies and procedures regarding collection, analysis, reporting, and dissemination activities, including unmasking procedures, and whether any such actions were based upon improper considerations. If circumstances warrant, the OIG will consider other issues that may arise during the review.

The development is significant considering the NSA publicly denied Carlson's accusations.

In a statement released the day after Carlson aired his claim, the NSA called it "untrue." The spy agency said Carlson "has never been an intelligence target" of the NSA. However, the NSA did not deny potentially intercepting Carlson's communications in otherwise legal operations.

In fact, Axios reported last month that Carlson had been "talking to U.S.-based Kremlin intermediaries about setting up an interview with [Russian President] Vladimir Putin" shortly before he aired allegations that the NSA had spied on him. The context is important for this story because Carlson's alleged communications could have been inadvertently collected if he was communicating with someone on whom the NSA was gathering intelligence.

Still, there are safeguards if Americans are inadvertently swept up in NSA intelligence gathering operations.

Under such circumstances, the NSA is obligated to "mask" the identity of the American citizen. However, under special circumstances, especially those related to criminal activity or national security, the identity can be "unmasked" without the consent of the American citizen. Fewer than two dozen officials within the NSA have the authority to approve "unmasking," and, if approved, the identity of the unmasked American is only made available to the person who required it to carry out their job duty.

The NSA approves thousands of unmasking requests each year.

What did Fox News say?

A Fox News spokesperson said the network was "gratified" the incident is being internally investigated.

"We are gratified to learn the NSA's egregious surveillance of Tucker Carlson will now be independently investigated," the spokesperson said in a statement.

"As we have said, for the NSA to unmask Tucker Carlson or any journalist attempting to secure a newsworthy interview is entirely unacceptable and raises serious questions about their activities as well as their original denial, which was wildly misleading," the statement added.