Baku, December 26, AZERTAC Suspected North Korean drones crossed the inter-Korean border Monday without South Korea's permission, officials here said, prompting the deployment of fighter jets, choppers and other assets to shoot them down, according to Yonhap News Agency.The South's military detected multiple "unidentified objects," presumed to be unmanned aerial vehicles, in border areas of Gyeonggi Province from 10:25 a.m., according to an official at the Joint Chiefs of Staff.The vehicles flew across the Military Demarcation Line separating the two Koreas, and were spotted flying in those areas in Gimpo, Ganghwa Island and Paju, leading to temporary suspensions of civilian flights.The South issued warning messages, fired warning shots, and scrambled fighters, attack helicopters and other warplanes to remove them, while it remains unconfirmed whether the vehicles carry any weapons, the official said."We also identified them with our eyes," the JCS official told reporters on condition of anonymity. "An operation is still ongoing against the vehicles."The military also deployed a KA-1 light attack aircraft, but for an unknown reason, it crashed in Hoengseong County, about 140 kilometers east of Seoul, at 11:39 a.m. Both of the pilots escaped safely.The North's drone operations have been a source of growing security concerns here, as they could be used for spy operations, as well as potential attack missions against the South.The South announced its discovery of North Korean drone operations south of the border in 2014 and 2017, sounding an alarm against security threats posed by those unmanned vehicles.The latest violation of the South's territorial air raised tensions anew after the North fired two short-range ballistic missiles Friday and two medium-range ballistic missiles five days earlier.