(CNN) — Labeling the Obama administration's investigation of the September 2012 Benghazi attacks "simply unacceptable," eight Republican lawmakers are demanding more aggressive steps from the new FBI Director James Comey and asking that he brief Congress within 30 days.
"It has been more than 10 months since the attacks," the GOP lawmakers said in a draft of a letter to Comey obtained by CNN. "We appear to be no closer to knowing who was responsible today than we were in the early weeks following the attack. This is simply unacceptable."
The letter was initiated by GOP Rep. Jason Chaffetz of Utah and Sen. Lindsey Graham of South Carolina, two of the fiercest critics of the administration's Benghazi response. Others who have agreed to sign the missive to Comey include Sens. John McCain of Arizona, Kelly Ayotte of New Hampshire and Ron Johnson of Wisconsin. On the House side, GOP Reps. Darrell Issa, the chairman of the committee leading the House Benghazi investigation, Trey Gowdy of South Carolina and Jim Jordan of Ohio, signed the letter.
The eight GOP lawmakers signed off on the text of the letter late Tuesday, and planned to send it to Director Comey on Wednesday or Thursday, according to GOP sources who provided the draft to CNN on condition of anonymity because the final timing decision has not been made.
"Rumors continue to swirl about the whereabouts of suspects involved in the attack," the lawmakers write in their letter to Comey, who was just confirmed to replace Robert Mueller as FBI director. "The FBI continues to add pictures of potential assailants to its website and asks the Libyan people to assist with identifying the alleged perpetrators. We struggle to understand why we don't know more about those who attacked two U.S. compounds and murdered four brave Americans. "
Among those identified as a suspect or person of high interest from the hours after the Sept. 11, 2012 attack -- by both U.S. and Libyan officials -- is Ahmed Abu Khattalah, the founder of the Islamist organization Ansar al-Sharia. But in a recent conversation with CNN's Arwa Damon, Khattalah acknowledged being at the U.S. diplomatic mission after the attack but denied any involvement. In that conversation -- in Benghazi -- Khattalah told CNN he has not been questioned by either Libyan authorities or the FBI.
In their letter, the lawmakers write, "We encourage you to be aggressive in your investigation to properly hold accountable those who attacked our compounds in Benghazi. We owe the families of those killed, and the people of this nation, answers to who Lettas responsible and ensure they are held accountable."
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