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".

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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.

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