SEOUL, South Korea — At dawn, South Korean special forces packed into a small boat approached a hijacked freighter in the Arabian Sea. Commandos scrambled up a ladder onto the ship, aboard which Somali pirates were armed with AK assault rifles and anti-tank missiles. A South Korean destroyer and hovering Lynx helicopter provided covering fire.

When Friday’s operation ended five hours later, 21 hostages had been rescued, eight Somali pirates killed and five assailants captured. Pockmarks from artillery fire blanketed the ship’s bridge. One of the hostages was wounded, but all were alive — a remarkable ending for a risky rescue. Only a handful of rescues in recent years have involved such peril to the crew.

A wife of one of the South Korean crew cried in gratitude as the weeklong hijacking came to an end.

"Family members couldn’t sleep or eat well and prayed for a safe return. I am very relieved," she said, according to Yonhap news agency.

The daring and rare raid — what the South’s president called a "perfect operation" — handed South Korea a stunning success in the battle against pirates who have long tormented shipping in the waters between Africa and the Arabian peninsula.

It was also a triumph for President Lee Myung-bak, whose government suffered harsh criticism at home in the weeks following a North Korean attack in November on a South Korean island near disputed waters. Critics said Lee’s military was too slow and weak in its response to the attack, which killed two marines and two civilians.

Friday’s operation in waters between Oman and Africa came a week after the Somali attackers seized the Samho Jewelry, a 11,500-ton chemical carrier, as it was sailing from the United Arab Emirates to Sri Lanka.

During the rescue, the South Korean captain was shot by a pirate. He was taken by a U.S. helicopter to a nearby country for treatment, but the wound is not life-threatening, Lt. Gen. Lee Sung-ho told reporters. The 20 other crew members — seven South Koreans, two Indonesians and 11 citizens from Myanmar — were rescued unharmed and were in good condition, he said. South Korea’s Joint Chiefs of Staff said the destroyer was accompanying the vessel to a safe area; it didn’t elaborate.

"We will not tolerate any behavior that threatens the lives and safety of our people in the future," President Lee said in a brief televised statement.

Other countries’ special forces have launched several raids to rescue pirated ships in the past few months, but only once they were assured the crew was locked in a safe room, commonly referred to as a "citadel." Those rescues happened just hours, not days, after capture; they were launched as soon as the crew’s safety was confirmed.

The raid on the South Korean Samho Jewelry was rare because it happened a week after the ship was seized; it was not clear if the crew was in a citadel on Friday, but at least the wounded captain was not. Militaries are usually reluctant to launch such raids because of the risk of harm to hostages. A French rescue in 2009 that came two days after a sailboat was taken left one hostage dead.

Friday’s raid marked the first rescue operation by a South Korean navy vessel that has been deployed in the Gulf of Aden to help fight piracy since 2009.

"This operation demonstrated our government’s strong will to never negotiate with pirates," Gen. Lee said.

Countries have different criteria for deciding whether to launch raids, said Graeme Gibbon-Brooks, the head of Dryad Maritime Intelligence, which provides information about piracy to shipping companies. Some countries are aggressive, but others consider that the risk of hostages being caught in a crossfire was greater than the risk of waiting out the hijackers.

But he said it’s unlikely the pirates would try to retaliate by harming other crews.

That "would be spectacularly unwise. Somalis are known for being good business people and I think that that would lead to very a quick collapse of their business model," he said.

Somalia has not had a functioning government since 1991, during which time piracy has flourished off its coast, sometimes yielding multimillion-dollar ransoms. The ransoms the pirates get are among the few sources of income for small businesses that supply the pirates with food and other goods.

There are now 29 vessels and 703 hostages being held by pirates off the coast of Somalia. The country lies next to one of the world’s most important shipping routes, which connects the Indian Ocean to the Suez Canal and the Mediterranean Sea beyond.

The Bahrain-based U.S. 5th Fleet referred all questions to South Korea, although it said the U.S. Navy was aware of the rescue. Samho Shipping did not respond to a request for comment Friday.

The Samho Jewelry was the second vessel from South Korea-based Samho Shipping to be hijacked in the past several months.

In November, Somali pirates freed the supertanker Samho Dream and its 24 crew — five South Koreans and 19 Filipinos — after seven months of captivity. A company official said a ransom was paid that local media said was around $9 million.

In April 2009, a French navy commando team stormed the yacht Tanit. The shootout killed two pirates and one French hostage and freed four French citizens. The order for the rescue came after the pirates threatened to kill the hostages.

In the same year, U.S. navy snipers also shot three pirates who were holding an American captain hostage in a lifeboat after they had abandoned a larger ship, the Maersk Alabama.

___

AP writers Katharine Houreld in Nairobi, Kenya, and Foster Klug in Seoul contributed to this report.