A US Seventh Fleet investigation has determined that
the Seawolf-class fast-attack submarine USS Connecticut "grounded on an uncharted seamount while operating in international waters in the Indo-Pacific region" in early October.
USNI News cited unnamed sources as saying that the submarine's ballast tanks were damaged as a result of the incident, which prompted the Connecticut "to make a week-long voyage on the surface from the South China Sea to Guam".
Aside from Beijing, the contested waters of the South China Sea are claimed by a number of countries, such as the Philippines, Brunei, Malaysia, and Vietnam. The US has no claims to the area, but it often conducts so-called "freedom of navigation" missions there, which are slammed by Beijing as provocations.
The sources' remarks came after the Chinese Defence Ministry said last month that Beijing was gravely concerned about the recent incident with a US nuclear submarine in the Indo-Pacific, demanding that Washington provide the full details of the accident.
"We noticed that the US military deliberately delayed and concealed the details of the incident. Such irresponsible and secretive practice, lacking transparency, could easily lead to misunderstanding and miscalculation", Tan added.
According to the spokesman, Washington's actions have seriously threatened regional security and navigation safety, as well as exacerbated regional tensions. Tan urged the US to stop reconnaissance near China's borders and to give a detailed account of the incident "as soon as possible" to assuage the concerns of nations in the region.
In October, the US Navy said that the Connecticut struck an unknown object while operating in international waters in the Indo-Pacific region and that 11 sailors received moderate to minor injuries in the incident. The navy added that the submarine remains in safe and stable condition, and that the vessel's nuclear reactor and propulsion system remain unaffected and fully operational.