One of the Libyan militants suspected of carrying out the 2012 terrorist attack in Benghazi is now in federal custody and faced a federal judge Saturday.

Ahmed Abu Khattala, a suspected ringleader of the terrorist attack that killed four Americans, is the first of the alleged terrorists involved in the attack to be apprehended by U.S. officials, according to The Washington Post. He faces many criminal charges in the Sept. 11, 2012, killings of U.S. Ambassador J. Christopher Stevens, information officer Sean Smith and former Navy SEALs Glen Doherty and Tyrone Woods.

Stevens, 52, was the first U.S. ambassador to be killed on duty since 1979.

Khattala was transported from Libya to the USS New York, where he was first held after he was captured June 15.

A law enforcement official said Khattala was questioned during his journey to the U.S.

The official said Khattala was taken off the ship and flown to a landing area near the Washington Navy Yard. He was then fingerprinted and photographed at a federal courthouse.

He was arraigned in open court Saturday afternoon. Khattala had not been informed of the right to remain silent and to be represented by a lawyer for more than a week because of a "public safety" exception to the right. On Saturday, law enforcement officials confirmed he'd been informed of those rights days ago and "continued talking with investigators afterward."

His capture is a huge success for the Obama administration, which has been investigating the attack for nearly two years since President Barack Obama promised the men who carried out the attacks would be captured and tried in U.S. court.

Two days after he was captured, Khattala was charged with "killing a person during an attack on a federal facility, providing support to terrorists and a weapons offense."

The U.S. attorney's office filed more than 12 criminal complaints stemming from the attack in Benghazi, but the charges against Khattala are the only ones that have been publicly released.

The evidence against Khattala includes pictures and video from the attack, as well as testimony from witnesses. According to a U.S. official, evidence also includes the planners of the attack boasting about their involvement in the killings.

Khattala is being held at a federal courthouse in D.C. with tight security.

U.S. officials said they continue to hunt for Khattala's co-conspirators in the attack.

Khattala, a prominent member of terrorist groups in Benghazi, said in an interview with The Associated Press in January that he was at the U.S. embassy in Benghazi when it was attacked in 2012. However, he said he was trying to rescue people who were trapped after the attack.

The Obama administration will try Khattala, although many congressional Republicans are calling for Khattala to be sent to the Guantanamo Bay detention facility.

It is not the first time the Obama administration has captured a suspected terrorist overseas; other suspected terrorists have been captured and interrogated by U.S. officials before being brought to the U.S. to face criminal charges.