The US has identified five suspects connected with last year's attack on the diplomatic mission in Benghazi, Libya, but officials say they want to collect more proof before making arrests, the Associated Press learned.
Preparations for a raid to grab the men — now under constant surveillance — have been made, and under laws passed after 9/11, the United States could be legally justified in using military force to seize those it believes are linked to Al Qaeda and terrorist attacks.
"On the military side we have the evidence to enact a military strike for the head guy right now. We have voice, visual pid, talk traffic, etc.," an unidentified source told Fox News' Greta Van Susteren, though the Associated Press cited officials saying they lacked evidence for a drone strike.
However, the White House prefers a civilian court trial, suggesting the Obama administration may have foregone the option of detaining the suspected terrorists in prisons like Guantanamo Bay, which President Barack Obama has repeatedly said should be closed.
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US intelligence agencies believe the suspects are linked to Ansar al-Shariah, a Libyan militia group whose members were seen near the US diplomatic mission before the Sept. 11, 2012 attack that killed US Ambassador Chris Stevens and three other Americans.
The attempt at a civilian trial may also reveal a desire by the White House to refrain from treating the suspects as enemy combatants, favoring a more transparent judicial process, in which suspects are tried in their native countries or extradited to US criminal courts.
Many human rights organizations will likely favor the move away from military clandestine capture and detention. Human Rights Watch has previously criticized the indefinite detention of suspected terrorists without trial and the use of military commissions at Guantanamo Bay, which it says violates international law. On May 20, to mark the 100th day of a hunger strike at the prison, a number of rights organizations signed and sent a petition to Obama, asking him to "fulfill his promise to close Guantanamo."
But some US lawmakers have voiced their opposition to the administration's gesture towards a trial in a civilian courtroom.
Rep. Howard P. McKeon, Republican chairman of the House Armed Services Committee, said he is worried the White House mistakes the Benghazi attack for a criminal act, instead of an act of war. "The war on terror, I think, is a war and at times I get the feeling that the administration wants to treat it as a crime," McKeon said Tuesday.
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Last week, Attorney General Eric Holder told US lawmakers the inquiry had made significant progress, despite a reduced US presence in a restive post-revolutionary Libya and security risks that have hindered investigators.
"Regardless of what happened previously, we have made very, very, very substantial progress in that investigation," Attorney General Eric Holder told Congress, hinting of new developments. "The investigation is ongoing, that we are at a point where we have taken steps that I would say are definitive, concrete, and we are - we will be prepared shortly I think to reveal all that we have done.
Last month, Secretary of State John Kerry made a similar remark.
"They [the FBI] do have people ID'd," Kerry said. "They have made some progress. They have a number of suspects who are persons of interest that they are pursuing in this and building cases on."