South Korean navy commandos stormed a ship hijacked by Somali pirates in the Indian Ocean, rescuing all the crew and killing eight pirates, according to military officials.

“Our special forces stormed the hijacked Samho Jewelry earlier Friday and freed all hostages,” said Colonel Lee Bung-Woo, a spokesman for the Joint Chiefs of Staff.

“During the operation, our forces killed some Somali pirates and all of the hostages were confirmed alive,” Lee told reporters on Friday. Another JSC spokesman said eight pirates were killed.

The rescue took place about 1,300 kilometers (800 miles) off northeast Somalia, Lee said.

The South Korean skipper of the chemical freighter suffered a gunshot wound to his stomach during the raid but his condition is not life-threatening, Lee said.

The pirates seized the 11,500-ton ship and 21 crew members — eight South Koreans, two Indonesians and 11 from Myanmar — on January 15 in the Arabian Sea when it was en route to Sri Lanka from the United Arab Emirates.

Seoul ordered a destroyer on patrol in the Gulf of Aden to give chase and President Lee Myung-Bak ordered “all possible measures” to save the crew.

The military said Friday’s rescue followed a brief gunbattle Tuesday, when the destroyer encountered pirates who had apparently left the South Korean freighter to try to seize a nearby Mongolian vessel.

The South Korean commandos aboard a speedboat and a Lynx helicopter were dispatched to rescue the Mongolian ship.

Tuesday’s firefight left several pirates missing and believed killed although their bodies have not been found, spokesmen said. Three commandos were slightly hurt.

On Friday the South Koreans, supported by an Oman naval vessel, stormed the chemical tanker.

The rescue was seen as a morale boost for the South’s military, which was strongly criticised for its perceived weak response to North Korea’s shelling of a border island last November.

President Lee praised the troops for the operation, which he described as a complete success.