Submarine expert Dominiques Salles said in May the sinking could have been caused by a US nuclear attack submarine.

BBC: France probes US submarine link to fishing boat sinking

The 97m (318ft)-long craft is the UK's newest nuclear-powered attack submarine and joined the Royal Navy fleet in August 2010.

BBC: Able Seaman Ryan Samuel Donovan

In an exhibition marking the 80th anniversary, Beijing's Military Museum displays what Chinese official websites say is a model of a new nuclear-powered attack submarine, the Shang.

ECONOMIST: China's military might

The proposed plan would retire seven cruisers early, delay construction of the next large-deck amphibious warfare ship by one year, cancel the second Virginia-class nuclear-powered attack submarine (SSN) in 2014, delay construction of two smaller amphibious warfare ships, and reduce procurement of littoral combat ships by two and joint high speed vessels by eight.

CENTERFORSECURITYPOLICY: Section IV: Building a Two-MRC Force for the 21st Century

The Type-093 Shang-class nuclear attack boat and the Type-094 Jin-class nuclear ballistic missile submarine, represent the basis of the nuclear submarine programs.

CENTERFORSECURITYPOLICY: China's assymetrical strategy

On Hainan Island it has built a new, large naval base with underground submarine pens, which can support both strategic and nuclear-attack submarines.

CENTERFORSECURITYPOLICY: Enter the dragon

The building of underground submarine pens on Hainan Island, which can house both strategic and nuclear-attack submarines, cannot go unnoticed.

CENTERFORSECURITYPOLICY: Underestimating China