The Democratic People's Republic of Korea (DPRK) fired about 10 missiles of various types, including short-range ballistic missiles, westward and eastward, Yonhap news agency reported Wednesday, citing the Republic of Korea's (ROK) Joint Chiefs of Staff (JCS).

The JCS previously confirmed that three short-range ballistic missiles were fired, including one that dropped into waters 57 kilometers east of the ROK's eastern city of Sokcho, and another that headed toward Ulleung Island before falling into the water, prompting local authorities to issue an air raid alert.

It was the first time a DPRK ballistic missile had landed near the ROK waters, JCS said. 

"We declare that our military will respond decisively to this," it said. "Our military vowed to respond firmly to this (provocation)."

In wake of the event, South Korean President Yoon Suk-yeol called a meeting of the National Security Council and ordered "swift and stern measures so that DPRK's provocations pay a clear price."

Japan also confirmed DPRK's missile launches, with Prime Minister Fumio Kishida telling reporters he planned to call a "national security meeting as soon as possible."

Pyongyang's Wednesday launch came as the ROK and the U.S. on Monday started a five-day large-scale combined air drills "Vigilant Storm."

On Tuesday, the DPRK blasted the drills as "an aggressive and provocative military exercise thoroughly aimed at the DPRK," saying a grave situation is being created in the Korean Peninsula due to the excessive military confrontation of "the hostile forces."

"If the United States and South Korea attempt to use arms against us without fear, the special means of the armed forces of the DPRK will immediately perform their strategic mission and the United States and South Korea will face a shocking incident and pay the most terrible price in history," Pak Jong Chon, secretary of the Central Committee of the Workers' Party of Korea, said in a statement on Tuesday.