The Sept. 11 assault left four Americans dead, including U.S. Ambassador Chris Stevens.
Khattalah, the head of the group Ansar al-Sharia, has long said he was present at the U.S. compound the night of the incident, although he denied he had any role in the attack.
Schiff also commented on the closing of U.S. embassies around the world and the global terror alert issued over the weekend, saying that “the threat is very real.”
“We have a fairly high degree of confidence that there is an active plot afoot that’s of grave danger to our personnel,” Schiff said. “And for that reason, I think members on both sides of the aisle view the steps taken by the administration in closing these embassies as very prudent steps.”