North Korea launches several ballistic missiles towards the Sea of Japan

It added: "Our military has strengthened surveillance and vigilance in anticipation of any potential additional launches."

The Japanese Ministry of Defense, for its part, confirmed detecting the launch of at least one ballistic missile suspected to be North Korean.

The Joint Chiefs of Staff noted that some of the missiles detected traveled a distance of more than 900 kilometers, adding that South Korea and the United States are conducting an analysis to determine their exact specifications.

The South Korean National Security Office held an emergency meeting following the launch to assess the country's military readiness level.

This came days after North Korea tested a medium-range hypersonic missile.

Pyongyang said that the launch it conducted on October 3 involved the use of artificial intelligence.

It added that its missile is "capable of changing its flight path at a low altitude."

Days later, South Korea conducted its first test launch of a domestically developed hypersonic missile.

The presidential Blue House said in a statement that "President Lee Jae-myung monitored this afternoon the first test launch of a hypersonic glide vehicle, which is currently being researched and developed using domestic technology."

It added that this weapons system represents a "key strategic capability that can change the course of battle," and that "the unpredictable flight paths of the warheads and their immense speed allow them to strike key strategic targets."

Hypersonic glide vehicles are propelled into the upper layers of the atmosphere by booster rockets, then glide toward their targets at speeds five times the speed of sound or more.

Tensions between the two Koreas have escalated since three South Korean soldiers were wounded by the explosion of two landmines inside the Demilitarized Zone.