The Korean military reported that a North Korean drone had penetrated the designated airspace of the presidential office that forbids airborne traffic.

Officials in the military had stated that a drone from North Korea flew into a restricted area of a 3.7km radius surrounding the presidential office in Seoul, South Korea when it breached the nation’s airspace last month.

On Dec. 26, five North Korean drones crossed the boundary into South Korea, which prompted the South Korean military to react instantly by dispatching fighter planes and helicopters. However, despite the military’s efforts, they could not bring down the drones that remained in South Korean air space for several hours.

A military individual informed South Korea’s Yonhap News Agency on Thursday that the drone flew for a short time to the northern border of the area but did not get too close to important security sites.