(SEOUL, South Korea) -- North Korea test-launched four short-range missiles into the waters off its eastern coast on Thursday.
Experts believe the Scud-type missiles were fired to protest joint U.S.-South Korean military exercises that began on Monday.
The launch comes as North and South Korea shared two rounds of reunions for relatives separated during the Korean War.
"This is just a wake-up call for those who might have thought that North Korea is loosening up", said Lee Jung-Hoon, professor of international relations at Yonsei University in South Korea. "The test-launch of these short-range missiles is a typical North Korean pattern of seemingly coming to the table with good intentions, but then the very next day they engage in some sort of hostile act."
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