The missile in question stoked concern in Tokyo, triggering a rare warning from Japan's J-Alert emergency broadcasting system covering the prefectures of Niigata, Yamagata and Miyagi. But despite an initial Japanese government warning that the missile had overflown the country, Tokyo later reversed course, saying it had, in fact, lost track of the first missile over the Sea of Japan. "We detected a launch that had showed the potential to fly over Japan, and therefore triggered the J-Alert," Defense Minister Yasukazu Hamada told a news conference. "But, after checking the flight, we confirmed that it had not passed over Japan." Hamada said the ministry had estimated that the first missile fired had traveled 750 kilometers, but had hit a maximum altitude of 2,000 km. Such firings, known as "lofted" launches, have been conducted by the North to avoid overflying neighboring nations and to test the resilience of warheads. South Korea's military also confirmed the launches, saying that the first missile appeared to be of an ICBM, the South's Yonhap news agency reported. It said it believed the two other launches were of short-range ballistic missiles. Yonhap, quoting an unidentified source, earlier reported that the first missile had gone through a stage separation, suggesting it may have been a longer-range weapon.