US data in Iranian hands after downed drone?

The 10-week investigation into the downing of a CIA drone in Iran is raising questions as to whether the malfunctions inadvertently may have handed the Iranians not only the aircraft but its data.

Based on the review, a former intelligence official told Fox News that investigators think one of the drone's three major "data streams" began sending back bad information to its U.S.-based operator.

A leading question is whether the bad data caused the drone's operator to inadvertently land the aircraft.

But it also raises the possibility that the faulty data stream could have prevented the drone from dumping the intelligence it had collected. When a drone malfunctions, it is programmed to dump data so it does not fall into the wrong hands.

A former intelligence official confirmed to Fox News that the CIA's comprehensive review has been unable to replicate the specific malfunction that brought down the drone in Iran. Contact was lost with the drone and its operators on Nov. 29.

A congressional official, also familiar with the CIA review, said: "We have looked at this eight ways to Sunday. I can tell you it was a U.S. technical problem. The information (data) was not lining up and it was not the result of Iranian interference or jamming."

While efforts to reproduce or replicate the malfunction have failed, investigators are now focusing on how to prevent a repeat in the future -- but without the hardware or the drone itself, those efforts have been challenging.

While the former intelligence official said the Iranians do not have the ability to integrate the multiple data streams on the drone platform, the loss of the CIA drone could allow Tehran to gather information about materials and hardware. The intelligence data is thought to be encrypted and not easily accessed, the official said.

A CIA spokesman declined to comment for this story.

Fox News chief intelligence correspondent Catherine Herridge's bestselling book "The Next Wave: On the Hunt for al Qaeda's American Recruits" was published last year by Crown.