North Korea has blown up parts of roads and railway lines heading for the border dividing the peninsula, according to South Korea’s military, as tense relations between the two neighbors sour further.

“The North Korean military conducted detonations, assumed to be aimed at cutting off the Gyeongui and Donghae roads, at around noon and is carrying out additional activities using heavy equipment,” Seoul’s Joint Chiefs of Staff said in a statement reported by local media on Tuesday.

South Korea then fired warning shots on its side of the border, according to its military.

Pyongyang had warned earlier this month that it was planning to “completely separate” road and railway access to its southern neighbor.

This is a breaking story and will be updated shortly.

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