North Korea fired a ballistic missile off its east coast on Tuesday, South Korea's Joint Chiefs of Staff and the Japanese coast guard said.
As Reuters reported, the Japanese government warned citizens to take cover as the missile appears to have flown over and past its territory before falling into the Pacific ocean.
The incident was confirmed by the government of South Korea.
According to NHK, residents in Aomori and Hokkaido cities, located in the northern region of Japan, have been advised to be on alert and to notify police or fire officials if debris is seen. People were also warned by officials not to touch or pick up any debris.
The office of Japanese Prime Minister Fumio Kishida has begun to gather members to analyze the situation.
Officials are gathering information and will work South Korea and the U.S.
"North Korea's actions threaten Japan and the international community," the spokesperson said. "Missile launches like this go against the U.N. resolutions. Japan will launch a strong protest against North Korea in light of this. All new information will be shared promptly."
North Korea's Fifth Ballistic Missiles Test in 10 days
The latest launch was Pyongyang's fifth in 10 days. Last week, South Korean and Japanese officials announced that North Korea has fired two short-range ballistic missiles from the Pyongyang area towards the country's east coast.
Japan's NHK national television said multiple missiles were fired from North Korea on Saturday morning and were believed to have landed in the Sea of Japan, though outside of Japan's exclusive economic zone.
"What appears to be a ballistic missile was launched from North Korea," the Japanese coastguard said in a statement issued on Saturday.
In a second statement issued about 15 minutes later, the coastguard said another apparent ballistic missile was launched.
NHK said the projectiles seemed to have fallen outside Japan's exclusive economic zones, citing government sources.
The office of Japan's Prime Minister Fumio Kishida tweeted that the latest missile launch was being analysed and instructions issued for the safety of people, aircraft and vessels.
North Korea fired short-range ballistic missiles into the sea on Wednesday and Thursday in the hours before and after a visit by US Vice President Kamala Harris to South Korea during which she emphasised the "ironclad" United States commitment to the security of its Asian allies.
Japan's Vice Defence Minister Toshiro Ino said North Korea's repeated missile firings are "persistently escalating provocations".
"North Korea's actions threaten the peace and safety not only for Japan but also the region and the international community, and are absolutely impermissible," Ino said, calling the four launches in one week "unprecedented".