North Korean drones crossed the inter-Korean border and violated South Korean airspace for five hours on Monday, but the South Korean military failed to shoot them down.

According to the Joint Chiefs of Staff(JCS), multiple unmanned aerial vehicles(UAVs) presumed to be North Korean drones were detected in border areas of Gyeonggi Province from 10:25 a.m.

The drones reportedly flew across the Military Demarcation Line and were spotted flying over the areas of Gimpo, Ganghwa Island and Paju city in Gyeonggi Province.

The South Korean military detected a total of five drones, with one of them flying between Gimpo and Paju and traveling as far as the northern part of the capital of Seoul before returning to the North about three hours later.

The other four reportedly approached the west of Ganghwa Island and flew over the area. They are said to have been just briefly detected by the South Korean surveillance assets.

The South Korean military responded by firing warning shots and launching fighter planes and attack helicopters to neutralize the North Korean drones. The attack helicopters fired a combined 100 rounds but failed to shoot them down.

Lee Seung-o, director of operations at the JCS, said in a press briefing that this was a clear act of provocation by North Korea that encroached upon South Korea's territorial airspace.