North and South Korea were involved in a rare exchange of gunfire in the Demilitarised Zone (DMZ) which divides the two countries.
Seoul’s military said shots from the North hit a South Korean guard post in the central border town of Cheorwon.
It said it delivered a warning announcement and returned fire, adding that there are no reports of injuries.
While it is not clear what led the North to open fire, such incidents across the world’s most heavily fortified border are rare – the last occurred in 2017.
Military officials in the South say there was no sign of unusual troop movements from their neighbours.
The timing of the escalation is rather curious, as it comes bare 24 hours since the North Korean leader Kim Jong-un re-appeared after a 21-day absence that led many to think he was dead.
The demilitarised zone (DMZ) was set up after the Korean War in 1953 in order to create a buffer zone between the two countries.