North Korea fired a rocket at South Korea’s loudspeakers installed on the western frontline on Thursday, sharply raising military tensions that have already been heightened in the wake of the Aug. 4 land mine attack.

“At around 3:52 p.m., we detected what is presumed to be a trajectory of North Korea’s rocket. We are still analyzing it and there is no damage to our loudspeakers,” Seoul’s Defense Ministry said in a press release.

After the land mine incident that injured two South Korean troops, Seoul authorities resumed propaganda broadcasts through loudspeakers near the tense inter-Korean border. The communist state has denied responsibility and warned of “military action” against South Korean broadcasts.

The spike in tensions came as the two sides struggled to find momentum to reconcile as they mark the 70th anniversary of their liberation from Japan’s colonial rule.

By Song Sang-ho (sshluck@heraldcorp.com)