The South Korean navy has carried out a dramatic raid to rescue the crew of a cargo ship hijacked by Somali pirates in the Arabian Sea.

Navy commandos approached the 11,500-tonne Samho Jewelry in the early hours of the morning nearly a week after it was captured - there were fears the pirates were about to be joined by a mothership.

With back-up from a US warship in the area, South Korean commandos stormed the ship, rescuing all 21 crew members - the ship's captain was shot in the stomach but his injury was not life-threatening, said officials.

Eight of the pirates fell overboard during the raid and were believed to have been killed. The five remaining hijackers were captured.

Lt Gen Lee Sung-ho of the Joint Chiefs of Staff said it had been a "perfect operation". He praised the ship's captain for winning time by steering the ship "in a serpentine manner" to prevent it being taken to Somalia.

The navy also seized a boat and weapons used by the pirates. The Samho Jewelry had been carrying a cargo of chemicals from the United Arab Emirates towards Sri Lanka when it was captured on 15 January.