Benghazi attack: Suspect pleads not guilty

WASHINGTON (KABC) -- The suspect in the 2012 Benghazi attack entered a not guilty plea during a brief appearance in federal court in Washington, D.C. on Saturday.

Ahmed Abu Khattalah listened through an interpreter as he was arraigned on one charge of conspiracy to provide material support and resources to a terrorist organization. He was represented by a federal public defender and is due in court again next week.

A criminal complaint filed last year that was unsealed after his capture charges Abu Khattalah with three terror-related crimes, including killing a person during an attack on a federal facility, a crime that can be punishable by death. Prosecutors are promising to bring a superseding indictment against Abu Khattalah for the remaining charges soon.

Security was heightened at the federal courthouse ahead of the arraignment, which happened on a rare Saturday session.

A U.S. official told ABC News Abu Khattalah was read Miranda Rights last week. He has been talking and continued to talk after being Mirandized. He has provided "useful" information, but has not offered any admissions of guilt, a source told ABC News.

The 2012 attacks in Benghazi claimed three American lives, including U.S. ambassador to Libya Chris Stevens.

U.S. Special Forces captured Abu Khattala in Libya two weeks ago, marking the first breakthrough in the investigation of the Benghazi attacks.

ABC News and the Associated Press contributed to this report.