North Korea has fired what appears to be a ballistic missile early Monday, South Korea’s military said, according to Yonhap.

The unidentified missile was fired from near the North Korean coastal city of Wonsan, Seoul’s Joint Chief of Staff (JCS) said. The missile flew in a easterly direction, sources said. South Korean President Moon Jae-in ordered officials to hold a meeting of national security council at 7:30 a.m.

The North Korean leader recently inspected the test-fire of a new type of anti-aircraft guided weapon system, ordering its mass-production and deployment to bolster its air supremacy, Pyongyang’s state media said Sunday.

The Korean Central News Agency (KCNA) said Kim Jong-un watched “the successful test” organized by the Academy of National Defence Science, without revealing the date and location.

Kim told the Korean People’s Army (KPA) officials and those at the academy that the weapon system’s capability has been upgraded compared with last year in terms of efficiency to detect and track targets, as well as strike accuracy, according to the KCNA.

Kim previously guided the test of an anti-air guided weapon system in April 2016, and the latest test appears to be focusing on improving its surface-to-air guided missiles deployed last year.

“Some defects in the weapon system, discovered last year, were perfectly overcome to stand the test,” Kim was quoted as saying in English by the KCNA. “This weapon system, whose operation capability has been thoroughly verified, should be mass-produced to deploy in all over the country like forests so as to completely spoil the enemy’s wild dream to command the air, boasting of air supremacy and weapon almighty.”

Kim also emphasized that the communist nation should also pursue the development of a “next generation” anti-aircraft guided weapon system, according to the KCNA.

The KCNA said Kim was accompanied by Hwang Pyong-so, director of the general political bureau of the KPA, and Ri Yong-gil, vice chief of the KPA general staff.