PYONGYANG - The Democratic People's Republic of Korea on Wednesday conducted a test-fire of new-type high-altitude long-range anti-air missiles under development in the East Sea of Korea, the official Korean Central News Agency reported Thursday.

Kim Jong-un, general secretary of the Workers' Party of Korea and president of the State Affairs of the DPRK, observed the test-fire, said the report.

This is the first test-fire for estimating the tactical and technical features of the anti-air missile system in development, it said, adding that the launched missiles "accurately hit the mock targets".

The test-fire is part of the routine activities of the DPRK missile administration and its affiliated anti-air weapon system research institutes for the technical optimization of the national anti-air defense means, said the report.

Meanwhile, Kim guided the building of an 8,700-tonnage nuclear-powered strategic guided missile submarine on the spot, according to the KCNA's report.

Kim stressed the significance of building a strategic nuclear attack submarine, and "clarified the steadfast will and the strategic and tactical policy to steadily push forward with the nuclear weaponization of the navy", said the report.

He said that the Republic of Korea's nuclear submarine development plans would worsen instability on the Korean Peninsula.

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Kim also mentioned a strategic plan to reorganize the naval forces and establish new units, according to the report.