Officials said the military had spotted armed North Korean soldiers restoring damaged guard posts at several locations since November 24, based on photos taken by cameras and thermal optical equipment installed in the DMZ.

The development came after North Korea said on November 23 that it would resume all military measures suspended under the 2018 agreement, in response to Seoul's partial suspension of the agreement after Pyongyang launched a spy satellite.

The North-South pact, signed at a 2018 summit between North Korean leader Kim Jong-un and then-South Korean President Moon Jae-in, included a no-fly zone and a ban on live-fire military exercises near the border.

In addition, South Korea and North Korea each blew up 10 of the 11 guard posts in the DMZ to reduce tensions and prevent accidental clashes, leaving only one post of historical or other value.

“Only a few guard posts are being restored, but (North Korea) is expected to restore all of them as they are essential surveillance facilities,” a senior military official told reporters.

In response to North Korea's latest move, Seoul officials said they would closely monitor Pyongyang's activities.

“We are monitoring enemy movements and conducting search and ambush operations near old GP (guard posts) areas to monitor for further provocations,” the official said.