The U.S. watched as rifles, rocket-propelled grenades, and missiles flowed from Benghazi to Syrian ports where they would become part of the Islamic State's arsenal of weapons, a Defense Intelligence Agency memo reveals.

Then-Secretary of State Hillary Clinton denied any knowledge of this when Sen. Rand Paul, R-Ky asked her about it during a Benghazi hearing in January 2013. Think Progress said Paul's questions were "pushing a conspiracy theory."

Paul: "My question is, is the U.S. involved with any procuring of weapons, transfer of weapons, buying, selling, anyhow transferring weapons to Turkey out of Libya?"

Clinton: "To Turkey? I'll have to take that question for the record. That's, nobody's ever raised that with me."

Paul: "It's been in news reports that ships have been leaving from Libya and that they may have weapons. And what I'd like to know is, the annex that was close by, were they involved with procuring, buying, selling, obtaining weapons and were any of these weapons being transferred to other countries? Any countries, Turkey included?"

Clinton: "Well, senator, you'll have to direct that question to the agency that ran the annex. And, I will see what information is available."

Paul: "You're saying you don't know?"

Clinton: "I do not know. I don't have any information on that."

The Oct. 5, 2012, DIA memo, penned before the Benghazi attacks, makes it clear that the U.S. was watching as weapons were transferred from Benghazi to two Syrian ports.

"We played no role" in the moving of weapons from Syria, said former acting CIA director Michael Morell. "Whether we were watching other people do it, I can't talk about."

Morell's statement seems to confirm a Daily Telegraph report that the U.S. facilitated, through other countries, arms transfers to rebels that would become the Islamic State.

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The U.S. ran 75 airlifts and 3,000 tons of Yugoslav weapons to the rebels in November 2012, according to the Daily Telegraph: "The shipments were allegedly paid for by Saudi Arabia at the bidding of the United States, with assistance on supplying the weapons organised through Turkey and Jordan, Syria's neighbours."

At the same time, the U.S. gave Syria $1 billion in "humanitarian assistance," more than any other nation, with $250 million allocated directly to the Syrian rebels who would soon be known as the Islamic State, for what the State Department calls "non-lethal transition support."

Syrian activists interviewed by NPR say the $1 billion in taxpayer money was "almost invisible on the ground."