In a chilling admission that the world’s most dangerous terrorists now control some of the world’s most dangerous weapons, CIA Director John Brennan went on the record this week to warn that the leaders of the Islamic State are actively engaged in producing chemical weapons and using them on the battlefield.

Brennan told CBS News that the use of WMD by the terror state is limited for now. But he said ISIS appears to be trying to figure out how to use poison gas on a much wider scale.

It is, CBS reports, “a threat that keeps him up at night.”

This is not the first time we’ve seen open source news reports about ISIS’ chemical weapons capabilities (see here, here and here, as examples.) But Brennan is the highest-ranking U.S. intelligence official to confirm the Islamic State’s WMD capabilities.

The determination ISIS has to develop and deploy weapons that can kill on a mass…