The image which was first spotted by satellite imagery expert @rajfortyseven shows a Chinese Navy Type 091 Han class fast-attack submarine which is the first class of nuclear powered submarines deployed by China.
A nuclear powered submarine has an unlimited range of operations because their nuclear reactors rarely require refuelling. These submarines can be deployed underwater for extended durations and they are also difficult to track. Nuclear submarines are faster than the conventional diesel powered submarines. Diesel submarines operate for a shorter duration of a few weeks.
India has been saying that it is convinced about the presence of Chinese nuclear submarines in the Indian Ocean. Recently Navy Chief Sunil Lamba had said that the Indian Navy keeps a close watch and monitors movements of the Chinese submarines and ships. We launch surveillance missions in the form of aircraft and ships to keep a track of them, he had also said.
It may be recalled that last year Pakistan State Radio announced a deal to acquire 8 Chinese Yuan-class conventional diesel-electric powered submarines. The first four submarines are expected to be delivered by the end of 2023 while the others will be assembled in Karachi by 2028. This signalled the growing proximity between Pakistan and China which have been strengthening their naval links.