Now we know what happenned.
On April 25, 2003 the crew of a Chinese fishing boat noticed a strange sight—a periscope drifting listlessly above the surface of the water. The fishermen notified the People’s Liberation Army Navy (PLAN) which promptly dispatched two vessels to investigate.
At first the PLAN believed the contact to be an intruding submarine from South Korea or Japan. But when Chinese personnel finally recovered the apparent derelict they realized it was one of their own diesel-electric submarines, the Ming-class 361.
When they boarded on April 26, they found all seventy personnel slumped dead at their stations.
Military commissioner and former president Jiang Zemin acknowledged the tragic incident on May 2, 2003, in a statement honoring the sacrifice of Chinese sailors lives and vaguely characterizing the cause as “mechanical failure.”
A month later, an inquiry by his commission resulted in the dismissal of both the commander and commissar of the North Sea Fleet, and the demotion or dismissal of six or eight more officers for “improper command and control.” Jiang and President Hu Jintao later reportedly visited the recovered submarine and met with the families of the deceased.
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