One of the five North Korean drones that crossed the inter-Korean border and violated South Korean airspace on Monday is likely to have captured images of the presidential office before returning to the North.

According to military authorities on Tuesday, the first drone that was detected on Monday flew straight toward Seoul and returned to the North after some three hours.

The military believes this drone passed over Gimpo and Paju on its way to Seoul and headed back to the North through the northern part of the capital. The military, however, stopped short of elaborating on the northward route by which the aerial vehicle got out of the South.

One source raised the possibility that the drone managed to fly near Yongsan District and take photos of the presidential office before heading back.

The Joint Chiefs of Staff, however, said in a news briefing later in the day that the drone didn't fly above Yongsan. 

The latest incident has sparked criticism about the military’s anti-aircraft defense capability.

Although the Army’s Capital Defense Command introduced a system in 2019 to detect and neutralize unmanned aerial vehicles using secondary surveillance radar, the military failed to activate the system in the latest incident.