BAHRAIN, Bahraq—Sources close to the Pentagon say a U.S. unmanned aerial vehicle shot down by Iran on Thursday had penetrated deep into Iranian airspace.

While the U.S. Navy claims the RQ-4A Global Hawk was in international airspace, multiple sources with knowledge of the incident say the UAV had thrust so far into the country that “Iran's sensors must have been going crazy.”

“The UAV initially was just limping around over international waters, but something caught its operator’s eye and turned him on,” said one source who asked to remain anonymous. “From that point, the aircraft kept pushing deeper and deeper into their territory with no Iranian response. We couldn’t tell if they noticed us in there or not.”

Leaked maps of the drone’s flight path show it taking off from a top secret location near Oman commonly known as "the grundle." It then warmed up by making two large loops over the Gulf of Oman and Arabian peninsula before taking a hard turn north into a soft gap in Iran’s missile defenses.