North Korea on Friday fired into the Sea of Japan two projectiles that a South Korean military source said appeared to be short-range ballistic missiles, the latest in a series of such launches protesting U.S.-South Korea war games.

The projectiles were launched around 8:01 a.m. and 8:16 a.m. from Tongcheon County in Gangwon Province, South Korea's Joint Chiefs of Staff said.

They both flew about 230 kilometers, reaching a maximum altitude of about 30 kilometers and flying at a top speed of Mach 6.1, the JCS said in a statement, adding that South Korean and U.S. authorities are analyzing the missiles in depth.

It was the sixth launch of projectiles by the country since July 25, with the previous one occurring on Saturday when it fired what were also believed to be short-range ballistic missiles toward the Sea of Japan.

(Photo shows a projectile fired by North Korea on Aug. 10, 2019.)

South Korea's National Security Director Chung Eui Yong held an emergency meeting of the National Security Council, during which officials urged North Korea to stop such launches as they could escalate military tensions on the Korean Peninsula.

The latest launches are likely another warning against a South Korea-U.S. joint military drill that started last week and runs through late this month.

The Japanese government said that it has not confirmed any projectiles flying into Japan's exclusive economic zone and that the projectiles posed no immediate security threat.

"We will do all we can to ensure the safety of the people by working closely with the United States among others," Prime Minister Shinzo Abe told reporters after North Korea's latest launches.

Speaking to reporters in Tokyo, Japanese Defense Minister Takeshi Iwaya said, "The advancement of missile-related technology by North Korea is a very serious issue for the entire region and the international community. We will take all possible measures toward vigilance and surveillance."

North Korea did not immediately comment on the latest launches. However, earlier in the day, a North Korean state organ issued a statement harshly criticizing South Korean President Moon Jae In's appeal for inter-Korean cooperation and dialogue in a speech the previous day.

A spokesperson for the Committee for the Peaceful Reunification of the Country, a body that manages Inter-Korean relations, said in the statement Pyongyang has "nothing to talk any more with the south Korean authorities," according to the Korean Central News Agency.

"Even at this moment, there go on in south Korea joint military exercises against the DPRK. Does he have any face to talk about dialogue atmosphere, peaceful economy and peace-keeping mechanism," the statement said, reiterating the leadership's criticism of the exercises. DPRK is the acronym for North Korea's official name, the Democratic People's Republic of Korea.

Kim Eun Han, vice spokesman of South Korea's Unification Ministry, in response said at a regular briefing that the nation expresses "deep regret" that North Korea's criticism came right after Liberation Day, which is a joyous day for both Koreas.

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