South Korea says its troops have exchanged fire with North Korea along their tense land border.
The Joint Chiefs of Staff in Seoul said North Korean troops fired several bullets at a South Korean guard post inside the heavily fortified border between the countries on Sunday.
The military said in a statement South Korea fired two rounds in response after issuing a warning broadcast.
It said South Korea suffered no casualties.
Sunday’s fire exchange took place a day after North Korea reported its leader Kim Jong Un’s first public appearance in some 20 days amid intense speculation about his health.
The North Korean leader cut the ribbon at the opening of a fertiliser factory in Sunchon at a ceremony with other senior officials.
These included his sister Kim Yo Jong, who many analysts predict would take over if her brother is suddenly unable to rule.
State media said workers at the factory broke into “thunderous cheers” for Mr Kim, who it said is guiding the nation in a struggle to build a self-reliant economy in the face of “head wind” by “hostile forces”.
Mr Kim earlier vanished from the public eye after presiding over a Politburo meeting of the ruling Workers’ Party on April 11 to discuss the coronavirus.
Speculation about his health began swirling after he missed an April 15 event commemorating the birthday of his grandfather and state founder, Kim Il Sung, something he had never done since inheriting power upon his father Kim Jong Il’s death in late 2011.
The Koreas are split along the 155-mile long, 2.5-mile wide border called the Demilitarised Zone that was originally created as a buffer.
But despite its name, the DMZ is the world’s most heavily fortified border.
An estimated two million mines are peppered inside and near the DMZ, which is also guarded by barbed wire fences, tank traps and combat troops on both sides.
In late 2018, the two Koreas began destroying some of their front-line guard posts and removing mines from the DMZ as part of steps to reduce tensions.
But the efforts stalled amid a deadlock in nuclear negotiations between Kim and President Donald Trump meant to convince North Korea to give up its arsenal in exchange for lifting economic sanctions.
The last time there was gunfire along the border was in 2017, when North Korea sprayed bullets at a soldier fleeing to South Korea.