(VOVworld) - A Japanese government source said on Tuesday that there were signs of a potential North Korean ballistic missile launch. Defense Minister Gen Nakatani ordered the military to stay on alert to retaliate against any North Korean ballistic missile heading towards Japanese land or waters.

North Korean leader Kim Jong Un watches the ballistic rocket launch drill of the Strategic Force of the Korean People's Army (KPA) at an unknown location. (Photo: Reuters/KCNA)

According to a South Korean military source on Monday, North Korea appeared to have moved an intermediate-range missile to its east coast, but there were no signs of an imminent launch.

Regional tensions have been strained since North Korea’s 4^th nuclear test in January followed by a series of missile launches.