The US has filed charges against a Libyan man suspected of taking part in the deadly attack on the US consulate in Benghazi last year, say reports.
Militia chief Ahmed Abu Khattala was reportedly among those charged over the assault that killed the US ambassador Christopher Stevens and three others.
The filing was sealed and officials declined to comment on the reported charges. The New York Times said Mr Khattala was charged with murder.
Mr Khattala is not in custody.
An unknown number of other alleged attackers have also been charged, US media reported.
The US consulate in Benghazi, on the Libyan coast, was attacked by a militia on 11 September 2012.
The fighters stormed the diplomatic compound and set it ablaze. Stevens, another state department worker and two former Navy Seals were killed.
The US initially reported that the attack grew out of violent protests sparked by an anti-Islam film produced in the US, though it soon became clear it was an organised, pre-planned assault.
Republicans have denounced President Barack Obama's handling of the aftermath of the attack.
Members of the opposition party accused Mr Obama and his fellow Democrats of downplaying the attack in order to protect his re-election campaign.
The Republicans have also sought to link former Secretary of State Hillary Clinton, seen as a strong possible contender for the presidency in 2016, to the attack, suggesting without evidence that she was personally responsible for lapses in security.