North Korea has launched three short-range missiles into the Sea of Japan, apparently as part of a military drill, South Korea's defence ministry says.
"North Korea launched two guided missiles in the morning and another one in the afternoon," a defence ministry spokesman said.
"The missiles landed in the East Sea (Sea of Japan)," he said.
South Korea was maintaining intense surveillance of the North and keeping a high-level of readiness to deal with any risky developments, he added.
North Korea sometimes launches short-range missiles for tests or as part of military drills.
The launches followed a joint South Korea-US naval exercise this week, slammed by North Korea as a "wanton" provocation and rehearsal for war.
A US strike force led by the nuclear-powered aircraft carrier USS Nimitz participated in the two-day drill that ended on Tuesday.
A US defence official said last week that two North Korean missiles that had been primed for firing as tensions on the peninsula flared in the run-up to the North's national celebrations on April 15 had been moved from their launch site.
US and South Korean officials had been worried that any test of the Musudan medium-range missiles would trigger a fresh surge in tensions, which escalated after the North carried out a nuclear test in February.
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