Diver fights off shark in Sydney Harbour

The 31-year-old was brought to St Vincent's Hospital in a critical condition about 7:00am (AEDT), with severe injuries to his right hand and right thigh.

The hospital has not confirmed reports that the man lost his hand. It says he is in a serious but stable condition in intensive care.

The Navy says the specialist clearance diver was rushed to hospital from Woolloomooloo Bay, in Sydney's inner east, after being bitten off the naval base at Garden Island.

The Commander of the Australian Fleet, Rear Admiral Nigel Coates, says the 31-year-old was on the surface of the water with a police diver on the last day of an international counter-terrorism exercise.