The stricken NITC tanker Sanchi has sunk off China a week after a collision with a CoscoCS bulker, with the loss of all 32 crew.

State-owned China Central Television said that the burning 164,000-dwt vessel (built 2008) had gone down on Sunday after "suddenly igniting" at 0400 GMT.

Iran's Tasnim news agency said flames had spread to new condensate tanks, creating a blaze as high as 100 metres and temperatures of 350 degrees Celsius.