UPDATE: 2:47 a.m. EDT — The United States condemned North Korea’s latest firing of three ballistic missiles into the East Sea saying that the tests violate U.N. Security Council resolutions. Washington also said that such tests may pose a threat to aircraft and commercial ships in the region, according to the Associated Press.

The U.S. is planning to raise the issue during the East Asia summit in Laos later this week.

UPDATE: 1:57 a.m. EDT — The three ballistic missiles test-fired Monday by North Korea were medium-range Rodong-class and flew about 600 miles, according to South Korea’s military. A South Korean military official told Reuters that at least one of the missiles fell into Japan’s Air Defense Identification Zone.

Original story:

North Korea fired three ballistic missiles into the East Sea, South Korea’s Joint Chiefs of Staff (JCS) said Monday. 

The missiles were fired from Hwangju in North Hwanghae Province at around 12:14 p.m. local time (11:14 p.m. EDT Sunday) the JCS said, according to Yonhap New Agency. The type of missiles fired and how far they reached was not immediately known. The North’s state-run Korean Central News Agency did not confirm the latest development.

In June, North Korea tested its fifth and sixth intermediate-range ballistic missiles drawing condemnation from the U.S., South Korea and Japan. The U.N. Security Council called for the renewed enforcement of sanctions that were imposed after the reclusive country’s fourth nuclear test earlier this year.

The firing came a few hours after South Korean President Park Geun-hye and Chinese President Xi Jinping concluded a bilateral meeting on the sidelines of the G-20 summit in Hangzhou, China. The latest missile firing also comes after U.S. think tank 38 North reported last Thursday that the reclusive country’s navy is undergoing a facility and weapons upgrade on the east coast. The Kim Jong Un-led country has been trying to upgrade the Munchon Naval Base — the largest naval facility in the nation's east coast city of Wonsan. Once the upgrades are completed, it is expected to boost Pyongyang's navy’s capabilities for operational readiness, coastal defense and wartime amphibious special operation force against neighbor South Korea’s East Sea coast.