Washington: A tenth Somali man arrested on charges related to the hijacking of a yacht off the coast of Oman in February pleaded guilty on Thursday to piracy charges for the attack that left four Americans dead, US prosecutors said.
Mahdi Jama Mohamed was latest of the 15 individuals -- 14 from Somalia and one from Yemen -- arrested after the attack for their roles in the kidnapping and killings, to plead guilty in a federal court in the eastern state of Virginia.
"The pirates` greed for tens of thousands in ransom money ultimately led to the cold-blooded murder of the four US hostages off the coast of East Africa, said US attorney Neil MacBride in a statement.
"Modern-day pirates are dangerous criminals, not the swash-buckling rogues portrayed in Hollywood movies, and this latest guilty plea shows that attacks against American vessels will be met with swift justice in an American courtroom."
Mohamed, according to the FBI, was a "willing conspirator in the planned attack to hijack a vessel for ransom," and it was his own "avaricious behaviour" that led to his involvement in the plot.
The owners of the yacht Quest, Jean and Scott Adam, were Christian missionaries based in California who were sailing around the world at the time of the hijacking.
They were shot to death, along with their companions Bob Riggle and Phyllis Macay from Seattle, Washington, several days after being taken hostage and as negotiations were taking place with US Navy officials.
The guilty announcement is part of plea agreements that will allow them to avoid the death penalty, but face life in prison.
According to Mohamed`s plea agreement, US prosecutors said he admits joining the pirates that took the vessel, but said "he did not personally shoot any of the four Americans, nor did they instruct any other person to shoot the hostages”.
Plea deals allow defendants to seek reductions in their sentences.
Accused Somali pirate Mohammad Saaili Shibin, said to have been the chief negotiator in the hijacking, was indicted on charges related to the killings earlier this year.
US service members, who had been trailing the yacht during the hostage drama, boarded the vessel after hearing gunshots and discovered the Americans` bodies, according to US officials.
The US military said it had undertaken negotiations, led by Shibin, to secure the release of the hostages at the time the pirates fatally shot their captives.