North Korea on Saturday threatened to attack South Korean loudspeakers that are broadcasting anti-Pyongyang propaganda messages across their shared border, the world's most heavily armed, CTV reported.

The warning follows Pyongyang's earlier denial that it had planted land mines on the South Korean side of the Demilitarized Zone that injured two South Korean soldiers last week. Seoul retaliated for those injuries by restarting the loudspeaker propaganda broadcasts for the first time in 11 years and suggested more actions could follow.

The authoritarian North is extremely sensitive about insults of its leader, Kim Jong Un, and tries to isolate its people from any criticism or suggestions that Kim is anything other than powerful and revered.

North Korea's army said in a statement that the broadcasts are equivalent to a declaration of war and that a failure to immediately stop them and take down the loudspeakers would result in "an all-out military action of justice to blow up all means for 'anti-north psychological warfare"' on the front lines.