A group of 15 suspected pirates captured after the killing of four Americans on a hijacked yacht off Somalia could be sent to the US to face trial, the US military says.
The group is being held aboard the aircraft carrier USS Enterprise.
In the past year, at least six accused Somali pirates have been convicted in US courts.
US agencies are investigating the killings on Tuesday of Phyllis Macay, Bob Riggle, Jean and Scott Adam.
The US military, FBI and Justice Department are working on the next steps for their suspected killers, said Bob Prucha, a spokesman for US Central Command in Florida.
The four Americans were aboard the S/V Quest, the Adams' 58-foot ship, when they were hijacked on Friday in the waters off Oman.
A convoy of Navy ships, including the Enterprise, sped to their rescue.
According to the US military, two pirates came aboard a US Navy ship to negotiate the release of the hostages. A rocket-propelled grenade later launched toward the US Navy ships, missing, and the Navy sailors heard gunfire from the Quest.
A team of Navy Seal special forces sailors then boarded the Quest and found the four Americans dying from gunshot wounds.
They regained control of the yacht, killing two pirates in the process and capturing an additional 13 pirates, and found the bodies of two pirates who were already dead, the US Navy said.
But the BBC's Will Ross in Nairobi says the pirates' telling of the encounter differs from the US Navy's. The pirates report the US warship attacked first, killing two pirates, and the hostages were killed in retaliation.
In November, five young Somali men were convicted of piracy in an April attack on a US Navy ship they mistook for a merchant vessel. One has been sentenced to 30 years in prison and the others face a possible life sentence.
And last week, a Somali man who pleaded guilty to the April 2009 pirate attack on a US-flagged merchant ship was sentenced to more than 33 years in prison.