(CN) - A federal grand jury in Washington slapped Ahmed Abu Khatallah, a key suspect in the 2012 terrorist attacks on the U.S. Consulate in Benghazi, Libya, with 17 new charges - some of which carry the death penalty, the Justice Department said Tuesday.
The investigation into Khatallah, 43, has been ongoing since his arrest in Libya in June. The initial indictment included a charge of conspiracy to provide material support and resources to terrorists resulting in death, a charge that has been carried forward to Tuesday's superseding indictment.
The Sept. 11, 2012 attacks on the consulate in Benghazi killed four people, including Ambassador J. Christopher Stevens.
With the superseding indictment, Khatallah now faces charges of murdering an internationally protected person and murdering an officer and employee of the United States, aiding and abetting, several firearms and weapons charges, and malicious destruction of U.S. property, among others.
Four of the most serious charges carry the death penalty, while the others involve long prison terms. Khatallah will be arraigned in Washington on Oct. 20.
"These additional charges reflect Ahmed Abu Khatallah's integral role in the attack on U.S. facilities in Benghazi, which led to the deaths of four brave Americans," said U.S. Attorney General Eric Holder. "We will never relent in pursuing justice against those who commit heinous acts of terrorism against the United States. Those who would do harm to our citizens - no matter how far away - should understand that our nation's memory is long and our reach is far."
George Venizelos, the FBI's assistant director in charge of the New York field office handling the case, said the new charges underscore the ongoing investigation into Khatallah's role in the attack.
"With additional charges being announced today, Ahmed Abu Khatallah's role in the Benghazi attack is even clearer," Venizelos said. "As the charges allege, he was the leader of an extremist militia group who carried out this brutal act of violence that took the lives of four honorable Americans. The Benghazi investigation remains one of the FBI's top priorities and we will work tirelessly until all of those responsible are brought to justice."
According to the latest indictment, Khatallah commanded Ubaydah Bin Jarrah, an Islamist extremist militia in Benghazi bent on establishing Sharia law in Libya. That group merged with Ansar al-Sharia - another Islamist extremist group in Libya with the same goal - in 2011.
Besides Ambassador Stevens, the attack also killed State Department information management officer Sean Smith and two security contractors, Tyrone Woods and Glen Doherty.
The investigation into Khatallah's role in the Benghazi attack remains ongoing, the Justice Department said.
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