After a four-hour hearing, the five were "sentenced to life in prison plus 80 years," Peter Carr, a spokesman for the US attorney`s office in Virginia, told AFP.
The Somalis were convicted in November by a court in Virginia on charges of piracy, of attacking to plunder a maritime vessel and assault with a dangerous weapon for their roles in an attack in April on the USS Nichols.
Piracy carries a mandatory sentence in the United States of life in prison, while firearms charges carry sentences of 30 years to life.
Defense lawyers had contested the piracy conviction, arguing the Somalis were fishermen who had been forced to take part in the attack on the Nichols.
Their appeal was thrown out by a US federal judge last week.
The sentencing comes days after 13 other Somalis and one Yemeni were indicted by a US court for their roles in a pirate attack against a yacht with four Americans on board as it sailed off the coast of Somalia last month.
At least three of the defendants in that case stand accused of killing the retired US couple and two friends on the yacht, the S/V Quest.
They were the first US citizens to die in a spate of high-seas kidnappings in recent years that has focused world attention on the pirate-infested waters off Somalia. (*)
Editor: Kunto Wibisono
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