In a secret raid Sunday, U.S. special operations troops captured the suspected  ringleader of the 2012 attack against two American government facilities in Benghazi, Libya, putting a key figure in the deadly assault in U.S. hands for the first time, U.S. officials said Tuesday.

Ahmed Abu Khatallah was captured near Benghazi by U.S. troops working with the FBI and is en route to Washington, D.C., where he is expected to face federal charges that could bring the death penalty, according to a federal law enforcement official, speaking on condition of anonymity. The charges against him and 12 others who allegedly took part in the attack in Benghazi were filed a year ago by federal prosecutors in Washington.

He is not expected to make his first appearance in court until sometime next week, the official said.

In a statement, Pentagon officials described him as “a key figure in the attacks on U.S. facilities in Benghazi.”

There were no casualties in the raid and all U.S. personnel have left Libya, the statement said.

President Obama, in statement, said the capture "demonstrated that we will do whatever it takes to see that justice is done when people harm Americans."

Obama said the U.S. also remained committed to supporting the Libyan people "as they work to overcome years of tyranny and do the difficult work of building a democracy."

The law enforcement official said Khatallah was questioned initially about any new potential terror threats and was then read his Miranda rights. With Khatallah now in custody, prosecutors are likely to submit the case to a federal grand jury, which could bring additional charges.

The decision to try Khattalah in federal court could be controversial. Republicans have opposed bringing cases involving accused terrorists to civilian courts, and Sens. John McCain (R-Ariz.) and Lindsey Graham (R-S.C.) both said Tuesday that Khattalah should be sent to the military prison at Guantanamo Bay, Cuba.

But Obama and Atty. Gen. Eric Holder have argued that federal courts have repeatedly proven capable of handling such high-profile cases.

Khatallah’s capture is a major success for the administration, which has faced a steady drumbeat of criticism from Republicans since the Benghazi attacks  for failing to capture the perpetrators and for poor security at a U.S. diplomatic compound and a CIA base nearby.

Four Americans, including U.S. Ambassador J. Christopher Stevens, were killed that night when more than 60 attackers overwhelmed unarmed Libyan guards and stormed the compound, setting fire to the buildings and engaging in running gun battles with a few CIA and diplomatic security agents.

The FBI investigation of the incident was stalled for months by instability in Libya. The country's weak government ruled out extraditing its citizens to the U.S.

Until his capture, Khatallah continued to live freely in Libya while giving taunting interviews to major media outlets as recently as six months ago. The State Department designated Khatallah as a terrorist in January, describing him as a leader of Ansar al Sharia, a Libyan militant group that has been described as having links to Al Qaeda.

Benghazi, the hub of Libya’s east, has been beset by turmoil in recent months, and the chaos deepened last month when a rogue ex-general based in the city launched a self-declared war on Islamist armed groups, resulting in more than 100 deaths.

Khalifa Hiftar, who spent years in exile in the United States, has the support of some Libyan military units, and has used military aircraft to bombard the positions of Islamist militias. Even before Haftar’s offensive, assassinations and car bombings were common in Benghazi, most often taking aim at security targets.

This week, authorities ordered an overnight ban on vehicle traffic in the city in an effort to stem militia clashes that had been breaking out nightly as soon as darkness fell.

The circumstances surrounding the September 2012 Benghazi attack sparked a long-running partisan battle. A report earlier this year by House Republicans blamed the Obama administration for failing to beef up security.

But the same report debunked persistent claims about the response to the incident: that the U.S. military was ordered to "stand down" instead of going to the aid of Stevens and others. 

"There was no 'stand down' order issued to U.S. military personnel in Tripoli," the report said, blaming the claim on "confusion" about the facts arising from what it termed inadequate previous reviews.

Hillary Rodham Clinton, who was secretary of State at the time of the attack, has said repeatedly that she was responsible for the security of the diplomats in Benghazi.

On Sunday, questioned again about her role, she suggested that no additional explanation she offered would satisfy her critics.

"There's a difference between unanswered questions and unlistened-to answers,” Clinton told Jane Pauley in an interview on “CBS Sunday Morning.”

“There were a lot of confusing pieces of information flooding into us from the very first moment we heard about it,” Clinton said, referring to the attack on the U.S. diplomatic compound in Benghazi. “We did our best to sort it out."

"I did my best to fully cooperate with the Congress. I respect the Congress' oversight responsibility," she added, but suggested that Republican critics have seized on discrepancies that arose from “the fog of war” and have improperly tried to use them as evidence of a coverup.

Times staff writer Neela Banerjee contributed to this report

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