Japan’s Ministry of Defense said on July 21 that a Chinese naval vessel had conducted a machine-gun firing exercise two days earlier inside Japan’s claimed EEZ in the Pacific. It was first time the ministry has publicly announced a case involving a foreign warship conducting a live-fire exercise inside Japan’s EEZ. The Joint Staff later confirmed that the Kaifeng conducted the machine-gun firing roughly 180 kilometers southwest of the island, squarely inside Japan’s EEZ. He also revived China’s long-standing argument that Okinotorishima is a rock, not an island capable of generating an EEZ under UNCLOS Article 121. The legal disagreement therefore runs deeper than the question of whether military exercises are permissible in another state’s EEZ.