The Syrian News Agency SANA and Alikhbaria TV channel reported that a “hostile” drone was intercepted in northern Latakia, a regime-held city. This video is said to show some of the drone wreckage. U.S. officials have confirmed that the Predator drone crashed and believe it may have been shot down, but have not made a final determination. (YouTube/الوكالة العربية السورية للأنباء)

Crashing drones are spilling secrets about U.S. military operations.

A surveillance mission was exposed last week when a Predator drone crashed in northwest Syria while spying on the home turf of President Bashar al-Assad. U.S. officials believe the drone was shot down, but they haven’t ruled out mechanical failure. Regardless, the wreckage offered the first hard evidence of a U.S. confrontation with Assad’s forces.

The mishap in Syria follows a string of crashes in Yemen, another country where the U.S. military keeps virtually all details of its drone operations classified.

Yemeni tribesmen have reported three cases in the past 15 months in which U.S. drones have fallen from the sky, pulling back the curtain on likely surveillance targets. Air Force spokesmen said they could not confirm any crashes in Yemen, but Air Force records obtained by The Washington Post show the dates match up with official acknowledgments of accidents that occurred in classified locations.

Since January 2014, the Air Force has reported 14 crashes of Predator and Reaper drones that either destroyed the aircraft or inflicted more than $2 million in damage. Three of the accidents took place in Afghanistan, but six happened elsewhere in classified or undisclosed sites, a sharp increase from prior years.

The far-flung nature of the accidents reinforces how U.S. drone operations have spread well beyond the established war zone in Afghanistan.

In November, a Reaper drone crashed in the Sahara while returning to a new U.S. base in Niger. At the start of last year, a Predator plunged into the Mediterranean Sea after conducting a secret mission over Libya, a rare tangible sign of U.S. surveillance operations there.

U.S. military drones are also based in Turkey, Italy, Ethiopia, Kuwait, Qatar, the United Arab Emirates and Djibouti, a small country on the Horn of Africa. In addition, the CIA has its own drone bases in Saudi Arabia and Afghanistan.

The demand for U.S. military drones that are capable of conducting airstrikes continues to soar. Last year, Predators and Reapers flew more than ever: 369,913 flight hours, or six times the figure for 2006, according to Air Force statistics.

The Predator alone logged the third-most hours of any plane in the Air Force, ranking narrowly behind the F-16 fighter jet and the workhorse KC-135 refueling tanker.

Military planners had expected the opposite, that demand for drones would drop as U.S. troops withdrew from Afghanistan. Instead, the Pentagon became embroiled in a new conflict against the Islamic State in Iraq and Syria. Meanwhile, other terrorist threats have flared in Yemen, Somalia and North Africa, further taxing the U.S. drone fleet.

“We simply underestimated the continued demand,” Deputy Secretary of Defense Robert O. Work told a defense conference last week in Washington. “They quickly got sucked up in the unexpected campaign in Iraq and Syria.”

Commanders’ appetite for drones and other surveillance aircraft, he added, “remains very, very high and continues to outstrip our supply.”

In addition to keeping pilots out of harm’s way, drones such as the Predator and Reaper can instantly transmit full-motion video to intelligence analysts — a critical technology in modern warfare.

Video from drones “has become fundamental to almost all battlefield maneuvers,” said Army Gen. Lloyd Austin, the overall commander of U.S. forces in the Middle East and Afghanistan, in a prepared statement this month to the House Armed Services Committee. He said allies were chipping in with their drones and other reconnaissance aircraft but that “shortages do remain that will need to be addressed.”

The Pentagon is asking Congress for $904 million next year to buy 29 Reapers, more than double the number it had sought for this year. The Air Force says it has an acute need to replace drones that have crashed and to phase out the Predator, an older model that has less firepower and range than the Reaper.

The surge in drone flights has also strained the crews that operate them from the ground, forcing many to work six days a week. Faced with a shortage of remote-control pilots, the Air Force has stepped up recruiting and is planning to offer retention bonuses.

Reliability has long been the Achilles’ heel of drones. Although they malfunction less often than they used to, they still crash at a higher rate than other military aircraft. Of the 269 Predators acquired by the Air Force over the past two decades, more than half have wrecked in major accidents, records show.

Predators and Reapers generally fly at altitudes above 18,000 feet — too high for militants to shoot them down with small arms. But the slow-moving aircraft can be easy marks for missile batteries operated by regular armies.

On March 17, the U.S. Air Force lost contact with a Predator that had been flying a nighttime sortie near Latakia, Syria. While Assad’s forces had been happy to allow U.S. drones to target Islamic State fighters in other parts of the country, Latakia is an Assad stronghold.

Syrian state-run media reported that government air defenses shot down “a hostile aircraft” and showed pictures of the wreckage, including a stamped label from General Atomics, the California-based manufacturer of the Predator.

U.S. officials have not disputed that the drone could have been hit by a missile, but they have not ruled out other potential causes. A loss of electrical power and severed communications links are two other common factors in drone accidents.

The crash revealed something else. It would be extremely difficult for U.S. drones to reach northwestern Syria from their primary bases in the Persian Gulf. That meant the Predator had almost certainly entered Syrian airspace from Turkey.

The U.S. Air Force has Predators stationed at Incirlik Air Base, but the Turkish government has long insisted those drones are limited to flying surveillance missions over northern Iraq. The crash in Latakia was a clear sign that Turkish officials had secretly relaxed that rule and were permitting the Pentagon to use their territory for operations in Syria.