The missiles are believed to have been launched from North Korea’s eastern coast and fallen in the Japanese Sea. Japan confirmed that North Korea had fired missiles, but said none of them had landed in Japan’s territorial waters.

Analysts suggested that the missile launches were part of military drills. Pyongyang routinely test-launches such missiles, but the latest tests followed several weeks of relative calm on the Korean Peninsula after tensions escalated earlier this year, following North Korea’s test of a long-range Taepodong 2 missile in December and its third nuclear test in February, to which the UN responded with sanctions.

After the start of the Foal Eagle joint military exercises between South Korea and the US in March, North Korea threatened to carry out a nuclear attack on the US mainland and on US forces in the region, and tested two short-range missiles off the east coast of the Korean Peninsula. Later it denied entry to South Korean workers to the jointly run Kaesong industrial complex in North Korea, prompting South Korea to withdraw its remaining workers from the site.

Last week, reports emerged that two North Korean mid-range missiles, reportedly prepared for launch last month, had been withdrawn from their coastal positions.