WASHINGTON (AP) — A federal judge ordered a Libyan militant charged in the 2012 Benghazi attacks to remain in U.S. custody.

A lawyer for Ahmed Abu Khattala conceded in court Wednesday that it was appropriate for her client to remain locked up, given the nature of the charge he faces and his lack of ties to the United States.

This undated file image obtained from Facebook shows Ahmed Abu Khattala, an alleged leader of the deadly 2012 attacks on Americans in Benghazi, Libya, who was captured by U.S. special forces on Sunday, June 15, 2014, on the outskirts of Benghazi. (AP Photo, File)

But the attorney, Michelle Peterson, also argued that prosecutors had not yet presented evidence of his involvement in the Sept. 11, 2012 attacks that killed U.S. Ambassador Chris Stevens and three other Americans

Abu Khattala appeared briefly in federal court in Washington. He listened to the proceedings through headphones as an interpreter translated the conversation into Arabic.

Prosecutors filed court papers this week that outlined some details of their case. More could emerge when the Justice Department issues a new indictment.