Editor's note: This story has been updated (see below).

Publicly and privately, the Pentagon pinky-swears that militants haven't been able to make a dent in U.S. operations, even though they're able to tap into American overhead surveillance feeds. But at least one Air Force official, under the cover of anonymity, is telling a different story. One militant group in Iraq was able to stay a step ahead of U.S. forces, he says, thanks to their ability to intercept spy drones' transmissions.

"We noticed a trend when going after these guys; that sometimes they seemed to have better early warning," the officer tells *Air Force Times' *Michael Hoffman and John Reed.

Eventually, American troops were able to raid a safe house of the Kata'ib Hezbollah militia, based out of Baghdad's Sadr City. As Hoffman and Reed note, the group "has long been suspected of being a surrogate for Iran's Quds Force." U.S. forces were surprised at the level of technical sophistication. On confiscated laptops, they found footage taken by both Predator drones and the Army's fleet of smaller unmanned aerial vehicles, or UAVs.

The Army drones are the most vulnerable to interception, because they broadcast their feeds unencrypted and in every direction. Retrofitting the hand-held Raven UAVs will take "at least two years," Col. Gregory Gonzalez tells Hoffman. Locking up the Army's other drones may take even longer.

For the Shadow, Hunter, Warrior Alpha and the Extended-Range Multipurpose UAV, the Army will retrofit all systems with encryption, as funding permits, said Gonzalez.

According to the Air Force's Unmanned Aircraft Systems Flight Plan, the service has an objective of ensuring "protected communications" on its MQ-1 Predator and MQ-9 Reaper drones by 2014. "Both the MQ-1 and MQ-9 use the proprietary datalinks that are unencrypted and as such susceptible to

enemy exploitation," the Flight Plan notes.

UPDATE: So how important is this security hole, really? Check out the comments in this earlier Danger Room post for a well-informed debate.

UPDATE 2: Air Force officers told me last week that the intercepts were no big deal, because the interceptors were only seeing the raw video shot by the drone or spy plane. Without the metadata to go along with it, the footage was extremely hard to interpret. "As this is video only, it was assessed overall that this capability in the hands of our immediate adversaries posed limited threat to operations or capabilities," one officer e-mailed.

It turns out that intercepting the metadata isn't much harder than tapping the video itself. Because "there is also mission control data carried inside the satellite signal to the ground control stations," according to an analysis carried by Wikileaks. Everything from target locations to drone headings to sensor angles can be pulled off the satellite transmission, too. The more this security breach is examined, the bigger it becomes.

[Photo: USAF]

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