Warning shots fired at North Korean soldiers ahead of Putin's visit

The incident came as Russian President Vladimir Putin will visit North Korea on Tuesday and Wednesday for the first time in 24 years (Pictures: AP)

South Korean soldiers fired waring shots after dozens more North Korean troops crossed the Military Demarcation Line near the border on Tuesday.

Around 20 to 30 breached the line by 65 feet inside the demilitarised zone but quickly retreated, according to the South’s Joint Chiefs of Staff, who said they did not think it was intentional.

The military observed increased North Korean construction activities along their heavily armed border to install suspected anti-tank barriers, reinforce roads and plant land mines.

It appeared to be part of efforts to tighten border control and prevent North Koreans from defecting to the South, an official said.

The incident came as Russian President Vladimir Putin will visit North Korea on Tuesday and Wednesday for the first time in 24 years, according to the two countries.

Last week, South Korea’s military fired warning shots after around 20 North Korean soldiers briefly crossed the border, Seoul officials said.

A North Korean military guard post, top, and South Korean post, bottom (Picture: AP)

North Korean soldiers install their guard post in the Demilitarized Zone (DMZ) (Picture: AP)

North Korean soldiers working at an undisclosed location near the heavily fortified border (Picture: South Korean Defence Ministry/AFP)

The South’s military has said the border area is dense with overgrown trees and plants that may have obscured the visibility of North Korean soldiers and caused them to cross the border.

The Joint Chiefs of Staff said it suspects North Korea will expand its border construction activities, which started around April and is possibly aimed at making it harder for North Korean civilians or soldiers to defect to the South as Pyongyang’s leadership attempts to strengthen its control over its people.

‘Our military is closely monitoring North Korean military activities in the frontline area while guarding against accidental situations,’ the Joint Chiefs of Staff said in a statement.

The border intrusions come as tensions rise between the war-divided rivals, who in recent weeks have engaged in Cold War-style psychological warfare and made it clear they are no longer bound by their landmark military agreement in 2018 to reduce tensions.

The military observed increased activities along the border to install suspected anti-tank barriers, reinforce roads and plant land mines (Picture: South Korean Defence Ministry/AFP)

The Koreas’ heavily fortified border, referred to as the Demilitarized Zone, has occasionally been a site of bloodshed and violent confrontations between the rivals.

The military demarcation line marks the border between the two Koreas within the DMZ, which is 154 miles long and 2.5 miles wide.

The zone is strewn with an estimated two million mines and guarded by barbed wire fences, tank traps and combat troops on both sides.

It’s a legacy of the 1950-53 Korean War, which ended with an armistice, not a peace treaty.

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