The South Korean ministry in charge of inter-Korean affairs said that North Korea's reference of conducting a test simulating the mid-air detonation of a shell of the rocket launcher system could be the regime's insinuation of a possible use of tactical nuclear weapons in the future.

An official at Seoul's unification ministry said on Tuesday that the government, along with related agencies and countries, was keeping tabs on the situation.

The North's state media, including ruling party mouthpiece the Rodong Sinmun, earlier reported that North Korean leader Kim Jong-un oversaw the "salvo" drills of artillery units using the 600mm multiple rocket launch system the previous day, followed by the targeted midair detonation.

The KN-25, is classified as a short-range ballistic missile, which Pyongyang has claimed is capable of carrying a tactical nuclear warhead.
 
On Monday, the South Korean military detected the North's firing of multiple short-range ballistic missiles from near Pyongyang, in apparent response to the completion of Seoul and Washington's annual joint Freedom Shield military exercise.