Key commanders from every branch of the military held an emergency meeting Monday to discuss the recent infiltrations of unmanned aerial vehicles.
Defense Minister Kim Kwan-jin, who led the meeting, urged all of the military to be at the ready for any threat out of Pyongyang.
Kim emphasized that the three drones found in South Korea in recent days were for surveillance purposes, but warned that future ones may be used to carry out attacks.
North Korea has hundreds of unmanned aerial vehicles in its possession so there could very well be more found in South Korea in the coming days and weeks.
The South Korean military says it's well equipped to deal with enemy jet incursions and attack UAVs, but adds that it's much more difficult to detect these types of UAVs, which are very small in size.
Seoul says it plans to purchase low-altitude radar and other military gadgetry to prevent further infiltrations.
Seoul's Joint Chiefs of Staff said it will take strong actions over Pyongyang's violation of its airspace,.. and will also mobilize units across the country to search for other drones.
A third drone was found on a mountain in Samcheok, Gangwon Province, and was reported to the military authorities last Friday.
Initial investigations show the drone is the same model as the one that crashed in Paju late last month.
The South Korean military was unable to detect any of the UAVs, and has only learned of their existence because they crashed on South Korea soil.
The ministry says if the drones are confirmed to have come from the North, it would put Pyongyang in clear violation of not only the Korean armistice agreement, but also of an international agreement that forbids flying over another country's air space without prior notification.
Kim Hyun-bin Arirang News.