North Korean drones crossed the inter-Korean border on Monday, prompting South Korea to launch warplanes in response.

According to South Korea's 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 vehicles reportedly flew across the Military Demarcation Line and were spotted flying over the areas of Gimpo, Ganghwa Island and Paju city in Gyeonggi Province.

According to multiple sources in the government, some of the drones even flew over civilian residential areas of Paju and approached the capital of Seoul.

The military reportedly said that the drones were identifiable even with the naked eye, similar in size to that of North Korean drones found in South Korea in 2014, and attempts were made to shoot them down with the deployment of warplanes and attack helicopters.

An Air Force KA-1 light attack aircraft that crashed in Gangwon Province earlier on Monday is said to have had an accident while taking off to respond to the North Korean drones. Both of the plane's pilots ejected safely.

The encroachment marked the first time that North Korean UAVs crossed the border since June 2017, when a suspected North Korean drone was found crashed in a mountain in Inje, Gangwon Province.