(ABC NEWS) -- The U.S. government has captured who it’s calling “a key figure” in the attacks two years ago on U.S. facilities in Benghazi, Libya, which killed U.S. Ambassador Chris Stevens and three other Americans.
American military and law enforcement personnel operating in Libya captured Ahmed Abu Khattala, who has secretly been indicted in the U.S. for his alleged role in the attacks.
Khattala, who was captured Sunday, is now in “a secure location outside of Libya,” and no civilians or U.S. personnel were harmed in the operation, according to a statement today from a Pentagon spokesman. Two U.S. officials said he is being held on a U.S. Navy ship in the Mediterranean.
"It's important for us to send as a message to the world that when Americans are attacked, no matter how long it takes, we will find those responsible and bring them to justice," President Obama said today.
Khattala is expected to be questioned by a special team of U.S. interrogators for potential intelligence leads for the next few hours or possibly days, senior U.S. officials told ABC News, but eventually he will be tried in federal court in Washington, D.C.
A one-page criminal complaint against Khattala, unsealed today, accuses the militant of "killing a person in the course of an action on a federal facility," providing and conspiring to provide "material support to terrorists resulting in death" and using a firearm in relation to a violent crime. Attorney General Eric Holder said the U.S. reserves the right to add charges "in the coming days."
Pentagon Press Secretary Rear Admiral Jack Kirby told reporters today the Libyan government was notified of the operation, but declined to say exactly when. A spokesperson for the U.S. State Department said it was a "unilateral U.S. operation."
White House Press Secretary Jay Carney said the capture of Abu Khattala marks an “important milestone” in the search for those who perpetrated the attack in Benghazi.
Since the attack on Sept. 11, 2012, the Obama administration and top law enforcement officials have faced harsh criticism over the failure to capture anyone involved in the attack. Part of the criticism has focused on the fact that some reporters have been able to conduct in-person interviews with Khattala and suspects but the U.S. government had appeared unable to do the same.
Khattala told CBS News, for instance, he was there the night of the attack, but denied he had anything to do with it. He also dared the Libyan government to arrest him if they thought otherwise.
Testifying before a House panel last week, FBI Director James Comey said he takes "the Benghazi matter very, very seriously," and it is something the FBI has “made progress on.”
“One thing you got to know about the FBI, we never give up,” Comey added. “So sometimes things take longer than we'd like them to but they never go into an inactive bin.”
Kirby spoke to the amount of time it took the U.S. to grab Khattala.
"Terrorists go to great lengths to avoid capture and it can be a complicated process at getting them," Kirby told reporters. "You don't want to launch a complicated mission like this without all the proper information and resources in place. So what matters is not that it took a matter of time to get him, but that we got him."
Attorney General Holder said in a statement today that the U.S. has "conducted a thorough, unrelenting investigation, across continents, to find the perpetrators" and he "pledged" to identify and arrest any co-conspirators.
"This is our pledge; we owe it to the victims of the Benghazi attack and their loved ones nothing less," he said.
Last October an elite American Army Delta Force team snatched another terrorist suspect off the streets of Tripoli. That man, known as Anas al-Libi, was held aboard a Navy ship where he was interrogated by the U.S. government's High-Value Detainee Interrogation Group (HIG) before being transferred to New York for trial. He has pleaded not guilty.
ABC News' Lee Ferran contributed to this report.