A man suspected in the attacks two years ago on U.S. facilities in Benghazi, Libya, which killed U.S. Ambassador Chris Stevens and three other Americans arrived at federal court in Washington, D.C. today, a source told ABC News.
Ahmed Abu Khattala was captured in Libya earlier this month. He's expected to be arraigned later today, according to the source.
A criminal complaint filed against Khattala earlier this year was unsealed after his arrest and accused 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.
"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 after Khattala's capture.
After Khattala's capture, Pentagon Press Secretary Rear Admiral Jack Kirby told reporters that 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."
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."
U.S. officials questioned Khattala aboard a U.S. Navy ship before he arrived in Washington D.C.
ABC News' PIERRE THOMAS, LUIS MARTINEZ and LEE FERRAN contributed to this report.