"I believe the people clearly saw the danger of a North Korea policy that relied on North Korea's good intentions and military agreements. We had been planning to establish a drone unit to carry out surveillance and reconnaissance operations on North Korea's key military facilities, but in the wake of yesterday's incident, we will move up the drone unit's establishment as much as possible," Yoon was quoted as saying during a Cabinet meeting.
The South Korean leader criticized the administration of former president Moon Jae-in for pursuing peaceful policy based on diplomatic efforts and negotiations with North Korea, the agency said.
On Monday, media reported, citing South Korean military, that a number of drones believed to be North Korean had crossed the inter-Korean border. South Korea tried to shoot the drones down and scrambled fighter jets and attack helicopters to intercept them. One of the aircraft, a KA-1 light attack plane, reportedly crashed during takeoff.
Four small North Korean drones flew in the area of Ganghwado Island in South Korea, and another flew up to the northern region of the metropolitan agglomeration, including Seoul. Yonhap later said that one drone managed to return back to the North, while the remaining four disappeared from radars.
The South Korean Defense Ministry called the violation of its airspace by North Korean drones "a clear provocation" and pledged to respond decisively.