South and North Korean soldiers exchanged gunfire on Sunday along their sensitive frontier, South Korean military officials said, the first such skirmish since the two nations took drastic measures to ease border frictions. 

Every so often violent clashes erupted along the border, the most heavily defended in the world. Though the incident is a reminder of ongoing strains, it has caused no reported injuries on either side, and is unlikely to intensify, analysts claim.

The Joint Chiefs of Staff in Seoul disclosed that North Korean troops fired several rounds at a South Korean guardpost inside the border that separates the two nations at 7:41 a.m. on Sunday.

In retaliation, South Korean troops unleashed two rounds after sending out a warning broadcast, the military stated, adding no injuries were sustained.

In a statement, the South's military said they are taking actions through the inter-Korean communication lines to get a clearer understanding of the incident and to prevent any untoward incidents from happening again. "We also keep a necessary readiness posture," the statement added.

The Koreas are divided alongside the Demilitarized Zone originally created as a buffer between the two rival states. However, given what its name implies, the DMZ is the most highly fortified boundary in the world.

The incident on Sunday came one day after North Korean leader Kim Jong Un reportedly appeared in public for the first time in almost three weeks, dispelling reports that he was dead or severely ill.

KCNA said Kim and senior officials attended the ceremony Friday marking the completion of a fertilizer factory near Pyongyang. State TV showed Kim laughing around factory facilities and walking around.

Kim previously vanished from the public eye after chairing a ruling Workers' Party Politburo meeting on April 11 to discuss the ongoing global health crisis.

Speculation about his health began to circulate after he skipped an event on April 15 to commemorate the birthday of his grandfather, something he had never done after he inherited power over the death of his father, Kim Jong Il, in 2011.

The two Koreas dismantled some of their front-line guard posts in late 2018, and started clearing mines from the DMZ as part of tension mitigation measures. But the failed attempts in the middle of a deadlock in nuclear talks between Kim and US President Donald Trump were intended to force North Korea to abandon its arsenal.

Since the second Kim-Trump summit in Vietnam in early 2019 broke down due to disagreements over US-led sanctions against North Korea, the diplomacy has not made much headway.