The armed MQ-1 Predator was on a routine surveillance mission above international waters , 16 miles off the coast , the Defense Department said . The U.S. Navy has accounted for all its drones , a U.S. defense official says . A new report from the Government Accountability Office (GAO) found that the Pentagon is not tracking how many of its unmanned aircraft are in use and what missions they perform. The drone was seized as it flew over the Persian Gulf , Iranian state media says . Iran 's Revolutionary Guard says the drone was collecting data .
The U.S. Navy has accounted for all its drones , a U.S. defense official says . A new report from the Government Accountability Office (GAO) found that the Pentagon is not tracking how many of its unmanned aircraft are in use and what missions they perform. The drone was seized as it flew over the Persian Gulf , Iranian state media says . Iran 's Revolutionary Guard says the drone was collecting data .