Sep 10, 2014 - As President Obama laid out his “strategy” last night for dealing with the Islamic State of Iraq and Syria (ISIS), and as bipartisan leadership in Congress pushes to approve as much as $4 billion to arm Syrian “rebels,” it should be noted that the keystone to his anti-Assad policy — the “vetted moderate” Free Syrian Army (FSA) — is now admitting that they, too, are working with the Islamic State. - https://pjmedia.com/blog/vetted-moderate-free-syrian-army-commander-admits-alliance-with-isis-confirms-pj-media-reporting/
Sep 23, 2014 - A claim by Sen. Rand Paul, R-Ky., that some of the 600 tons of weapons the U.S. gave Syrian rebels last year ended up in the hands of ISIS is based on the Free Syrian Armys initial cooperation with a Syrian-backed coalition of Islamic Front fighters. - http://www.wnd.com/2014/09/u-s-weapons-for-fsa-ended-up-with-isis/
This despite receiving arms from the US. There are numerous reports of this. Here are a few:
Where do the arms go?