North Korea has conducted a series of night-time firing exercises along the West Sea, raising tensions in the highly volatile area near the maritime border.

On Wednesday, North Korea’s military informed Seoul that it would conduct firing drills in its maritime territory on the West Sea near the border, known as the Northern Limit Line, until Friday. This was followed by a series of live-fire exercises, including Thursday’s drill that took place from 7:10 p.m. to 9:40 p.m.

According to the Joint Chiefs of Staff, none of the 190 rounds fired from a warship and coastal artillery on Thursday landed in South Korean waters. The JCS had earlier warned that it would respond strongly to any shells landing in South Korean territory.

Night-time live firing exercises are unusual because it is difficult to determine precisely where the shells have landed and thus hard to judge accuracy. There is also the added risk of inviting a military response from Seoul should any of the shells land in South Korean territory.

The fact that Pyongyang proceeded with nighttime drills despite such concerns demonstrates that Pyongyang is aiming to strengthen its ability to conduct battles at night. The drills also raised tensions in the area of previous Naval exchanges between the South and the North by firing toward the South along the NLL.

Pyongyang’s move is especially provocative because it does not acknowledge the NLL, drawn up by the U.S.-led United Nations Command after the Korean War ended in a cease-fire: Pyongyang has demanded that the line be drawn farther south.

In recent weeks Pyongyang has been testing Seoul. On May 8, Pyongyang sent a message to the Blue House saying that it would fire at South Korean vessels that cross the NLL. The following day, it sent another message challenging Seoul to fight if it had the courage to do so.

There is no reason for our military to respond to such verbal provocations that are designed to incite rash actions. However, the military should stand ever ready to respond to North Korean aggression anywhere in the South, including the tense area in the West Sea.

The reign of terror gripping the North is symptomatic of a weak leadership. To further consolidate his power, North Korean leader Kim Jong-un may be tempted to resort to military aggression against the South. The government should be ready for any number of contingencies that may threaten the country’s security.