A U.S. Air Force MQ-9 Reaper drone has crashed in northern Syria, the service announced on Tuesday.
"The aircraft was flying a combat mission when positive control of the aircraft was lost," the release stated. "The remotely piloted aircraft crash was not due to enemy fire. There are no reports of civilian injuries or damage to civilian property at the crash site.
"The MQ-9 was destroyed by coalition aircraft and is not in enemy hands," according to the statement from Shaw Air Force Base in South Carolina.
The Air Force pledged to convene an investigation board to explore what caused the mishap.
It wasn't immediately clear how many drones the Air Force is operating in the country, where the U.S. is launching airstrikes and supporting ground missions against the Islamic State in Iraq and Syria, or ISIS.
President Barack Obama has authorized the deployment of about 4,000 U.S. troops for the campaign against ISIS. Last fall, the president approved sending about 50 Special Forces advisers into Syria and 250 more were authorized in April for the effort to retake Raqqa, the proclaimed capital of the group.
The Air Force as of Sept. 30 had a total of 165 MQ-9As in inventory, in addition to 130 MQ-1Bs, according to information previously released by the service. Taken together, the drones account for more than half of the service’s intelligence, surveillance and reconnaissance fleet.
The Reaper, nicknamed the "hunter-killer" for its ability to conduct both strike and surveillance missions, is the bigger brother to the MQ-1 Predator medium-altitude unmanned aerial vehicle, or UAV. Both systems are made by General Atomics Aeronautical Systems Inc. of San Diego.
The MQ-9 is able to fly up to 50,000 feet and 230 miles per hour -- twice as fast as the MQ-1 -- and is designed to carry a combination of such armament as AGM-114 Hellfire missiles, GBU-12 Paveway II and GBU-38 JDAM GPS-guided bombs.
The Air Force is considering adding more bases in the U.S. for two-person crews to fly the Reaper. The service has struggled in recent years to train an adequate number of drone pilots, who are in demand given the high operational tempo of the fleet.
--Richard Sisk contributed to this report.