While the existence of one explosive chamber has been known for some time, the NCRI claims a second device could be hidden at Iran’s Parchin military complex, or at another site somewhere in Iran.

The claims raise new questions about the status and extent of Iran’s nuclear progress as negotiations between Tehran and the West approach their Nov. 24 deadline.

New information about the purported explosive chambers—as well as Iran’s elaborate network of front companies and organizations meant to obfuscate this nuclear work—was released on the same day that the United Nations’ nuclear watchdog accused Iran of failing to address key questions about it’s nuclear program.