A U.S. Air Force MQ-9 Reaper drone was shot down Sunday over Yemen, U.S. Central Command officials confirmed to Military.com on Monday.

“We assess that an MQ-9 Unmanned Aerial Vehicle was shot down in western Yemen on Oct. 1, 2017,” Maj. Earl Brown, a spokesman for the command, said in an email.

Brown didn’t provide further details, saying the incident “is under investigation.” He later clarified it was a U.S. platform.

“The details on the specifics of the mission are not releasable for [operational security reasons] and we don’t want to get ahead of any investigation,” Brown said, when asked about the altitude, speed and direction of the UAV’s mission.

Yemen’s Houthi forces claimed they shot down the drone in the capital Sanaa. Local footage showed the crippled, fiery aircraft falling through the sky.

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Military.com Equipment Guide: MQ-9 Reaper

The medium-altitude drone made by General Atomics is a long-endurance remotely piloted aircraft predominantly used by the U.S. Air Force for intelligence, surveillance and reconnaissance flights along with strike missions.

Other operators include the United Kingdom and Italy.

Civil unrest has paralyzed the country amid ongoing airstrikes from the Saudi-led coalition.

The war began in spring 2015, when Houthi rebels — anti-government fighters aligned with ousted former president Ali Abdullah Saleh — were dislodged from their position near the port city of Aden by the coalition, which includes the United Arab Emirates, Egypt, Qatar and Kuwait.