GIVEN THE SECRECY SURROUNDING THE SINKING, details on the sub are sparse. The Pentagon identified it as nuclear-powered, in spite of the fact that all of China’s nuclear-powered submarines are currently built by the Bohai Shipyard in Huludao.

China’s newest nuclear-powered submarine sank pierside in the spring and the Chinese Navy tried to conceal the loss, according to two US defense officials.

Building a potent nuclear submarine force would help China tighten control over its peripheral waters and improve its ability to seize Taiwan.