April 19 (UPI) -- South Korea's Defense Ministry said North Korea test launched multiple, short-range ballistic missiles into the East Sea, also known as the Sea of Japan, Sunday morning.

"Detailed specifications are currently under close analysis by South Korean and U.S. intelligence authorities," officials in Seoul said in a statement, according to ABC News.

"Our military is closely monitoring North Korea's military activities under a firm combined defense posture and maintains an overwhelming capability and readiness to respond to any provocation."

The Japan Times said the Defense Ministry of Japan also confirmed the activity.

"North Korea's series of actions, including the repeated launches of ballistic missiles and other weapons, threaten the peace and security of Japan, the region and the international community," the ministry said in a statement.