North Korea on Tuesday fired multiple short-range ballistic missiles off its eastern coast, the South Korean military said.
Japan's Defense Ministry said the missiles were believed to have already come down at sea and there were no immediate reports of damage.
US eyes North Korean ICBM tests
The US said the launches posed no "immediate threat."
"While we have assessed that this event does not pose an immediate threat to US personnel, or territory, or to our allies, we continue to monitor the situation," US Indo-Pacific Command said in a statement.
The launches come days after North Korean leader Kim Jong Un supervised a test of the country's newest intercontinental ballistic missile designed to reach the US mainland. In response, the US flew a long-range B-1B bomber in a joint drill with South Korea and Japan on Sunday.
On Tuesday, Kim's powerful sister, Kim Yo Jong, accused Pyongyang's rivals of making "aggressive and adventuristic military threats."
Evidence of North Korean troops in Russia emerges
Missile launch ahead of US election
Since 2022, Pyongyang has ramped up its missile tests, defying international sanctions.
Analysts have said that the most recent series of launches are an attempt to grab American attention ahead of this week's US presidential election.
Monday's launch also comes as North Korea's Foreign Minister Choe Son Hui met with Russian President Vladimir Putin in the Kremlin.
According to US, South Korean and Ukrainian intelligence, Pyongyang is estimated to have sent between 10,000 and 12,000 troops to Russia to help with its war in Ukraine.
North Korea and Russia have deepend their cooperation since Moscow's invasion of Ukraine and the two countries signed a comprehensive strategic partnership treaty in June.
sdi/ab (Reuters, AP, dpa)