Pyongyang says the missiles it fired toward Japan were part of an exercise targeting US military bases there. It comes as the White House announced the deployment of the advanced THAAD anti-missile defense system to South Korea to guard against the North. The test launches of four missiles, fired by North Korea into the Sea of Japan on Monday morning, were a drill carried out by an army unit commissioned with attacking US military bases in Japan, the country's official news agency KCNA said Tuesday. North Korean leader Kim Jong-un personally supervised the drill, it said. The launch was preceded by threats of retaliation to the US-South Korea military drills. Pyongyang views the exercises as a preparation of an attack on North Korea. Meanwhile, the White House said Monday that a THAAD missile defense system will be stationed in South Korea to counter threats from the North. White House press secretary Sean Spicer described the Monday morning launches as consistent with Pyongyang's