A South Korean soldier
Photo: KIM HONG-JI / REUTERS
Five North Korean drones entered South Korean airspace on Monday, according to the South Korean military.
As a result, fighter jets and helicopters rose and tried to shoot down the drones.
It is the first confirmed flight of North Korean drones over South Korean territory since 2017.
"This is a clear act of provocation by the North violating our airspace," said Lee Seung O, a member of the South Korean General Staff.
One of the drones they had flown near the South Korean capital Seoul.
Warning shots were initially fired.
Lee left it open whether drones were actually hit and shot down.
The South Korean news agency Yonhap later reported, citing the general staff, that the military had fired about a hundred shots.
But no drone was shot down.
One of them returned to North Korea.
The other four have lost sight of the military.
According to Lee, in response to the use of drones, South Korean reconnaissance aircraft flew north to take aerial photographs similar to the drones.
The North Korean drones were small, about two meters long.
He did not give any further details about the equipment of the aircraft.
According to the Ministry of Transport in Seoul, before the air force was deployed, departures at Incheon and Gimpo airports were briefly suspended at the request of the military.
The interruption of the launches at noon lasted about an hour, said a representative of the ministry.
He did not provide any further information.
In 2017, a North Korean drone believed to be on a spy mission crashed and was found on a mountain near the border.
Three years earlier, a North Korean drone had been spotted on a South Korean border island.
Relations between South Korea and largely isolated communist North Korea have been strained for decades.
They have worsened as the North has been testing missiles with an unusual frequency of late and the new Conservative government in the South has announced a tough stance on the North.
South Korea and its ally the USA have responded to the North Korean missile tests with military maneuvers.
North Korea sees such exercises as preparation for an invasion.