North Korean leader Kimâu00c2u0080u00c2u0088Jong-un. Pic/AFP

Seoul/Tokyo: North Korea fired four ballistic missiles into the sea off Japan's northwest on Monday, angering South Korea and Japan, days after it promised retaliation over U.S.-South Korea military drills it sees as a preparation for war. South Korea's military said the missiles were unlikely to have been intercontinental ballistic missiles (ICBM), which can reach the United States.