Conflicting reports were emerging today about who fired first: pirates or the US Navy in an attack which resulted in the murder of four kidnapped yachtsmen off the coast of East Africa.

Vice Admiral Mark Fox said in a televised briefing that the violence started when a rocket-propelled grenade was fired from the Davidson 58ft pilot house cutter at the USS Sterett, a guided-missile destroyer which was 600 yards away. The RPG missed and almost immediately afterward small arms fire was heard coming from the yacht.

But this was contradicted by a Reuters report which had a telephone interview with two Somali pirates carried by Reuters.

‘Our colleagues called us this morning, that they were being attacked by a U.S. warship,’ a pirate who identified himself as Mohamud said.

‘The U.S. warship shot in the head two of my comrades who were on the deck of the yacht by the time they alerted us,’ Mohamud said. ‘This is the time we ordered the other comrades inside yacht to react — kill the four Americans because there was no other alternative — then our line got cut.’

‘The killing of those four Americans and our comrades is a fair game that has started. Everybody will react if his life is in danger. We should not agree to be killed and let the hostages be freed,’ a pirate called Hussein told Reuters from Hobyo, another Somali coastal pirate haven.

Another report from ECOTERRA International, a body which monitors piracy activity in the area, said the fight might have been started by one of the yachtsmen. Its spokesman said: ‘Analysts believe that an attack against the Somali hostage takers must have taken place either from the outside or staged by the one passenger on board, who was reportedly trusted to have certain “capabilities”.’

U.S. naval forces who were trailing the Americans’ captured yacht with four warships boarded the vessel after the shoot-out. They tried to provide lifesaving care to the Americans, but they died of their wounds, U.S. Central Command in Tampa, Florida said.

A member of a U.S. special operations force killed one of the pirates with a knife as he went inside the yacht, said Vice Admiral Mark Fox, commander of U.S. naval forces for the Central Command.

President Barack Obama, who was notified about the deaths at 0442 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.

A total of two pirates, including the one who was knifed, died during the ensuing confrontation and 13 were captured and detained, the Central Command said. The remains of two other pirates who had been dead for some time were also found.

Negotiations had been under way to try to win the release of the two couples on the pirated vessel Quest when the gunfire was heard, the U.S. military said.

Those killed were Jean and Scott Adam, of Marina del Rey near Los Angeles, and Phyllis Mackay and Bob Riggle, of Seattle, Washington.

Quest was the home of the Adams who had been sailing around the world since December 2004 with a yacht full of Bibles.

Pirates hijacked the Quest on Friday several hundred miles south of Oman. Fox said mariners are warned about travelling through the area because of the dangers of pirate attacks.

In total the U.S. said that 19 pirates were involved in the hijacking of the Quest.

At the Seattle Singles Yacht Club, where Riggle and Mackay were well known, Joe Grande said the two were ‘great sailors, good people. They were doing what they wanted to do, but that’s small comfort in the face of this.’

Only minutes before the military announced that the four Americans had died, a Somali pirate told The Associated Press by phone that if the yacht were attacked, ‘the hostages will be the first to go.’

‘Some pirates have even suggested rigging the yacht with land mines and explosives so as the whole yacht explodes with the first gunshot,’ said the pirate, who gave his name as Abdullahi Mohamed, who claimed to be a friend of the pirates holding the four Americans.

Graeme Gibbon-Brooks, the head of Dryad Maritime Intelligence, said he was confounded by the turn of events.

‘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,’ he said, adding that the pirates must realize that killing Americans would invite a military response.

The military said U.S. forces have been monitoring the Quest for about three days, since shortly after the Friday attack. Four Navy warships were involved, including the aircraft carrier USS Enterprise.

Last week a Somali pirate was sentenced to 33 years in prison by a New York court for the 2009 hijacking of the Maersk Alabama, a U.S. cargo vessel. That hijacking ended when Navy sharpshooters killed two pirates holding the ship’s captain.

A pirate in Somalia told the AP last week that pirates were more likely to attack Americans because of the verdict.

The killing of the four Americans appears to underscore an increasingly brutal and aggressive shift pirates have been showing toward hostages. The conventional wisdom in the shipping industry had been that Somali pirates are businessmen looking for a ransom payday, not insurgents looking to terrorize people.

Pirates – who currently hold 30 ships and more than 660 hostages – typically win a multimillion ransom for releasing their captives, a huge sum that is shared among investors and pirates. One ransom paid last year was reported as $9.5 million. Most ransoms are worth several million dollars.

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.

Mohamed, the pirate in Somalia, told AP that pirate leaders had been expecting the yacht to make landfall soon.

Five cars full of pirates were headed toward the pirate dens of Eyl and Gara’ad in anticipation of the Quest reaching land Monday, he said. Had the four reached land, they may have faced a long hostage ordeal like the 388 days that the British sailing couple Paul and Rachel Chandler spent in the hands of pirates. The two were released in November.

Omar Jamal, first secretary at Somalia’s mission at the U.N., sent his condolences to the families of the four Americans and called the deaths a tragic loss of life. Jamal said there is an urgent need to address the piracy problem.

The Adams ran a Bible ministry and have been distributing Bibles to schools and churches in remote villages in areas including the Fiji Islands, Alaska, New Zealand, Central America and French Polynesia.

To load a yacht like the SY QUEST on a cargo ship and to bring it to the Mediterranean from the Maldives – whereby such cargo vessel then could be protected by the navies – would cost US$37,700.

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