The Dalian maritime rescue center received a report from another vessel, the "Guangyuan", at 3:08 p. m. Tuesday, saying a ship had suddenly sunk one nautical mile ahead of it.

大连海上搜救中心在星期二下午3：08接到一艘名为“光远”号船只发来的报告说，在他们前方1海里处有一艘货船突然下沉。

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While the submarines did not technically violate international maritime law as they didn't enter the 12-nautical-mile territorial waters near the areas in question, their sighting rattled Japanese officials and led the government to issue a warning that an order deploying the military to maintain maritime security could be issued if submarines enter Japan's territorial waters.

WSJ: Japan on Alert Over Unidentified Submarines

While the submarines didn't violate international maritime law they didn't enter the 12-nautical-mile territorial waters near the areas in question their sightings rattled Japanese officials and led the government to issue a warning that an order deploying the military to maintain maritime security could be issued if submarines enter Japan's territorial waters.

WSJ: Japan on Alert Over Submarines Near Its Territorial Waters