"North Korea has detonated parts of the Gyeongui and Donghae roads north of the Military Demarcation Line at around noon," the Yonhap news agency quoted the Joint Chiefs of Staff (JCS) as saying.
The JCS added that it has increased its surveillance and readiness posture in response.
The two Koreas are connected by roads and railways along the Gyeongui Line, which links South Korea's western border city of Paju to North Korea's Kaesong and the Donghae Line along the east coast.
This move comes as North Korea continues to escalate inter-Korean tensions and eliminate remnants of unification efforts.
Late last year, North Korean leader Kim Jong Un characterised the two Koreas as "two hostile states," and the regime has since taken measures to dismantle inter-Korean land routes.
North Korea has also removed street lamps, planted mines along its side of the Gyeongui and Donghae roads and deployed troops to construct apparent anti-tank barriers and strengthen barbed wire defences within its side of the Demilitarised Zone separating the two Koreas.
-- BERNAMA
