The Bashir Assad regime in Syria is loading of some of its weapons with deadly nerve agents, and mixing together the chemical precursors needed to carry out a sarin-laced attack. But that may not be the biggest chemical threat Syria faces. There’s also an increasing chance that a terror group might get its hands on some of the planet’s most gruesome chemical arms.

Assad’s chemical corps have spent years buying up and experimenting with the chemicals needed to make the nerve agent sarin; not even an increasingly bloody civil war has kept the labs from running. Today, Syria-watchers in the U.S. government believe, these chemical engineers may be skilled enough in handling sarin that the nerve agent might remain deadly for up to a year. (“This is not a ‘move it or lose it’ situation,” one American official tells Danger Room.) And during that time, the sarin could be acquired by one of the Islamic extremists working in the loosely led rebel movement to topple the Assad regime. In other words: There’s the prospect of chemically armed terrorists emerging from the Syrian civil war.

“Uncertainties regarding this crisis are pervasive, yet at least one outcome is highly probable: terrorist acquisition of chemical weapons if the regime falls,” writes Federation of American Scientists analyst Charles Blair.