Ahmed Abu Khattala, the suspected leader of the 2012 attack against the U.S. diplomatic mission in Benghazi, Libya, has been indicted on 17 new charges by a federal grand jury in Washington, D.C.

If you remember, Khattala was captured by special forces in Libya back in June. He appeared in court later that month and pleaded not guilty to a single count of conspiring to provide material support and resources to terrorists.

The indictment made public today clarifies the extent to which the government believes Khattala was involved in the attack, which killed four Americans, including Ambassador Chris Stevens.

According to a press release from the Justice Department:

"The superseding indictment describes Khatallah's alleged role in the attacks at a U.S. diplomatic mission in Benghazi and a second U.S. facility there, known as the annex. According to the superseding indictment, Khatallah was a leader of an extremist militia group and he conspired with others to attack the facilities, kill U.S. citizens, destroy buildings and other property, and plunder materials, including documents, maps and computers containing sensitive information."The offenses that could carry death sentences include one count of murder of an internationally protected person; three counts of murder of an officer and employee of the United States; four counts of killing a person in the course of an attack on a federal facility involving the use of a firearm and a dangerous weapon; and two counts of maliciously damaging and destroying U.S. property by means of fire and an explosive causing death."

In the indictment, the U.S. alleges that Khatallah undertook the attack because he had learned the United States had two intelligence facilities in Benghazi.

"He viewed U.S. intelligence actions in Benghazi as illegal, and ... he was therefore going to do something about this facility," the indictment claims.

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