Seoul: A US military drone flew over an inter-Korean border region during combined drills with South Korea on Thursday, military officials said, prompting residents in the area to evacuate as a precaution. "Upon further verification, the unmanned vehicle was identified as a US military drone participating in a training exercise," an official from South Korea's Joint Chiefs of Staff (JCS) told reporters. "This incident occurred during bilateral training between US Marines and the Republic of Korea Marine Corps' 1st Marine Division," the USFK said, referring to South Korea by its official name. "US Marine Corps personnel are assessing the circumstances surrounding the incident, and continue to coordinate with our Republic of Korea Marine Corps partners and appropriate local authorities," it added. The JCS official declined to give further details, such as whether the drone flew over the no-fly zone under the now-suspended 2018 inter-Korean military pact with North Korea.