A suspected North Korean small unmanned aerial vehicle (UAV) made a reconnaissance flight over the deployment site of the Terminal High Altitude Area Defense (THAAD) battery, the South Korean military told media on Tuesday.

The South confirmed that the drone, which was discovered by local residents on June 9, took photos of the Seongju County area in North Gyeongsang Province, where the U.S.-made THAAD system is deployed.

On June 9, the South’s Joint Chiefs of Staff (JCS) announced that a joint investigation team was called to the scene after receiving a report that a small sized flight vehicle was found