By Tabassum Zakaria and Phil Stewart
WASHINGTON (Reuters) - A terrorism suspect grabbed in Libya by U.S. special forces will likely be held on a Navy ship until interrogators decide he has provided as much information as he is going to, and there are no legal constraints on how long that may be, experts said Tuesday.
But while the U.S. government is not running against a legal clock to hold al Qaeda suspect Nazih al-Ragye, it will not want to keep him too long on board the USS San Antonio at sea, which could prompt accusations of flouting Geneva Conventions, U.S. experts say.
Also known as Abu Anas al-Liby, he was snatched from the streets of Tripoli over the weekend and is being questioned on the ship by a specialized interrogation team for high-value suspects.
While the U.S. government has not said what the next step will be for Liby, experts say he is likely to be brought to stand trial in New York where there is a federal indictment against him.
In 2011, a Somali man suspected of helping al Qaeda, Ahmed Abdulkadir Warsame, was held on a U.S. Navy ship for questioning for over two months without being advised of any legal rights before being brought to New York City to face charges.
One U.S. official said there was no time constraint necessarily associated with Liby's confinement. He was being held on an amphibious transport dock ship that can transport helicopters and hundreds of Marines.
"It doesn't matter the length of time as long as (he's held) in a humane condition," the official said, speaking on condition of anonymity.
Senior al Qaeda operatives are subject to military detention under a 2001 authorization for the use of military force, and there is no requirement that they be held in a particular place, Stephen Vladeck, a professor at American University Washington College of Law, said.
"I do think the longer they hold him (on ship) the more they risk their legal position in a subsequent criminal case," he said. "That's the administration's calculation - that they want to hold him, but not so long that it's going to be really, really hard to get a judge to sign off when they ultimately do prosecute him."
U.S. government officials have also been very careful to say that no decision has been made on whether Liby will be tried in a civilian or a military court because such declarations might influence subsequent judicial proceedings, U.S. experts said.
The raid in Tripoli was carried out by the U.S. Army's special operations Delta Force rather than the CIA, which grabbed a suspect off the streets of Italy a decade ago in a famous case of a U.S. abduction of a terrorism suspect.
Hina Shamsi, director of the national security project at the American Civil Liberties Union, said the U.S. raid to grab Liby off the streets in a foreign country was the first reported "rendition" of its kind under the Obama administration.
President Barack Obama has little doubt of Liby's involvement in plots against Americans. The Libyan is accused in the 1998 bombings of the U.S. embassies in Kenya and Tanzania that killed 224 civilians.
"We know that Mr. al-Liby planned and helped execute plots that killed hundreds of people, a whole lot of Americans. And we have strong evidence of that. And he will be brought to justice," Obama told a news conference in the White House.
It remained unclear what precisely the Libyan government knew about the operation to snatch Liby and when exactly it was informed.
Libyan Prime Minister Ali Zeidan said Libyans accused of crimes should be tried at home but the raid in which Liby was grabbed in Tripoli would not harm ties with Washington.
Charles Stimson, a national security law expert at the Heritage Foundation, a conservative think tank, said he believed Liby could be held an extended period aboard the ship without any serious risk to the government's case against him in a criminal court.
"Will a long period of time, 20, 30, 60 days on the ship, unnecessarily complicate the ability to try him in federal court? I think the answer is no," he said.
The U.S. administration is not saying what the plan is for Liby other than to bring him to justice.
"The administration is worried that anything it says could be used later on to say the clock should have started the second they said we are going to prosecute him," Vladeck said.
State Department spokeswoman Marie Harf said the United States had been in touch with the International Committee of the Red Cross about Liby and "he's being treated humanely," but she declined to comment on the next step.
Daniel Benjamin, a scholar at Dartmouth College and former counterterrorism coordinator at the State Department, said operations in which the United States pursues criminal suspects overseas is not a new phenomenon.
"In the case of the Libya operation it puts the Obama administration square in a tradition that goes back to the Reagan administration of pursuing people for whom there are indictments and confirming the United States never gives up on any of these cases," he said.
(Editing by Alistair Bell and Cynthia Osterman)