Families of American sailors killed in the suicide bombing of the USS Cole warship are suing the government of Sudan, accusing it of aiding terrorism.
The suicide bombing tore a large hole in the hull of the USS Cole
They claim the African nation helped al-Qaeda, which was blamed for the attack, and are seeking damages of more than $100m through a Virginia court.
Sudan has tried to have the case dismissed, saying too much time had passed since the 2000 bombing.
Seventeen US sailors died and 39 were injured in the attack off Yemen.
'Sanctuary for terror'
Terrorism expert Lorenzo Vidino told the court in Norfolk, Virginia, that hundreds of terrorists from Yemen went to Sudan for training.
"Sudan - the whole country - was a perfect sanctuary," he said.
Louge Gunn, the father of Seaman Cherone Louis Gunn - one of the sailors killed in the bombing - told the court he considered committing suicide after being told of his son's death.
"It was the most devastating thing that had ever happened to me," Mr Gunn said.
"I felt like somebody had put their hand in the inside of my body and pulled my skin out."
The families claim the Sudanese government gave al-Qaeda and its leader, Osama Bin Laden, financial and technical support, allowing the group to establish training bases, run businesses and even use Sudanese diplomatic passports to carry explosives.
The Sudanese government insists there is no link with al-Qaeda - a view backed by one recent US government report.
But the families disagree. They hope to claim the damages from millions of dollars in Sudanese assets frozen in the US.
They also hope to make it prohibitively expensive for nations to become involved in terrorism, their lawyers say.