NAIROBI // Four Americans taken hostage by Somali pirates off East Africa were killed by their captors, the US military said, marking the first time US citizens have been killed in a wave of pirate attacks plaguing the Gulf of Aden and the Indian Ocean.
US naval forces boarded the yacht after hearing the gunfire and tried to save the Americans but they died of their wounds, the US Central Command said. Two pirates died during the confrontation and 13 were captured.
Negotiations had been under way to win the release of the two couples on the vessel, Quest, when the gunfire was heard. The Quest was the home of Jean and Scott Adam, from California, who had been sailing around the world since December 2004. The other couple were Phyllis Macay and Bob Riggle, of Seattle, Washington.
A pirate fired a rocket-propelled grenade at a US Navy destroyer shadowing a hijacked yacht with the Americans aboard on Tuesday. Then gunfire erupted, the military said. US special forces rushed to the yacht only to find the four Americans fatally wounded.
The experienced yacht enthusiasts were from California and Washington. One of the American couples on board had been sailing around the world since 2004 handing out Bibles.
Their deaths appear to underscore an increasingly brutal and aggressive shift pirates have been showing toward hostages.
A pirate who said his name was Muse Abdi said killing hostages "has now become part of our rules," and he referred to a pirate who was sentenced in a New York court last week to 33 years in prison for an attack in 2009 on the US cargo vessel the Maersk Alabama.
"From now on, anyone who tries to rescue the hostages in our hands will only collect dead bodies," he said. "It will never ever happen that hostages are rescued and we are hauled to prison."
Pirates had hijacked the 58-foot yacht Quest south of Oman on Friday. Since then, four US warships and sky-high drones shadowed the vessel's movement as pirates tried to sail it to the Somali shore. US officials negotiated with the captors via radio.
But at 8am East Africa time on Tuesday, a rocket-propelled grenade was fired from the Quest at the USS Sterett, a guided-missile destroyer 600 metres away. The RPG missed and almost immediately afterward small arms fire was heard coming from the yacht, said Vice Admiral Mark Fox, commander of the US 5th Fleet in Bahrain.
Several pirates then appeared on deck with their hands up. US naval forces boarded the vessel and tried to provide lifesaving care to the Americans, but they died, Vice Admiral Fox said. No US forces were injured or killed.
Thirteen pirates were captured and detained, and two other pirates had boarded the USS Sterett on Monday to negotiate, Vice Admiral Fox said.
A member of a US special operations force killed one of the pirates with a knife, Vice Admiral Fox said. A second pirate was also killed, and the bodies of two other pirates were discovered on board, bringing to 19 the total number of pirates involved. The US military did not say how those two died and it was not known if the pirates had fought among themselves.
Pirates have increased attacks off the coast of East Africa in recent years despite an international flotilla of warships dedicated to protecting vessels and stopping the pirate assaults.
But the conventional wisdom in the shipping industry had been that Somali pirates are businessmen looking for a multimillion-dollar ransom payday, not insurgents looking to terrorise people.
Graeme Gibbon-Brooks, the head of Dryad Maritime Intelligence, said: "We have heard threats against the lives of Americans before but it strikes me as being very, very unusual why they would kill hostages outright." Mr Gibbon-Brooks saidthat the pirates must realise that killing Americans would invite a military response.
President Barack Obama, who was notified about the deaths at 4.42 a.m. Washington time, had authorized the military on Saturday to use force in case of an imminent threat to the hostages, said White House spokesman Jay Carney.
The Quest was the home Jean and Scott Adam, of Marina del Rey, near Los Angeles. The two had been sailing around the world since December 2004. Phyllis Macay and Bob Riggle, of Seattle, Washington, had recently joined the Adamses.
Joe Grande of the Seattle Singles Yacht Club, where Riggle and Macay were members., said: "Great sailors, good people. They were doing what they wanted to do, but that's small comfort in the face of this."
Around Christmas the Quest joined the Blue Water Rally, an around-the-world race. But race organisers said the Quest recently left the race despite what Vice Admiral Fox said were warnings about the dangers of sailing in the Horn of Africa region.
The Blue Water Rally said in a statement on Tuesday that though yachtsmen are discouraged from sailing in the region, the only other choices are to sail around the stormy and dangerous tip of South Africa or sail back across the Pacific.
The Adamses were skilled and experienced sailors, having travelled from from Panama in 2005 to Fiji in 2007 and Cambodia last year. They most recently sailed from Thailand to Sri Lanka and India, and were on their way to Oman when captured.