A CIA investigation failed to discover what caused a US drone to come down in Iran late last year and raised fears it failed to dump sensitive data, FOX News Channel reported Friday.

A former intelligence official confirmed to FOX News that the CIA’s comprehensive, 10-week review was unable to replicate the malfunction that brought down the RQ-170 Sentinel drone in Iran.

Contact was lost with the drone and its operators Nov. 29.

Based on the review, investigators believe one of the drone’s three major data streams began sending back bad information to its US-based operator. A leading question is whether the bad data caused the drone’s operator to inadvertently land the unmanned aerial vehicle (UAV).

It raises the question of whether the faulty data stream meant the drone did not dump the intelligence that it collected. When the UAV malfunctions, it is programmed to dump data so it does not fall into the wrong hands.

“We have looked at this eight ways to Sunday. I can tell you it was a US technical problem. The information [data] was not lining up, and it was not the result of Iranian interference or jamming,” a congressional official familiar with the CIA review said.

Investigators were focusing on how to prevent a repeat of the incident in the future, but without the hardware or the drone — Iran refused to return it — those efforts have been frustrated.

(Source: Newscore)