Simply WMDs from Iraq that weren’t shipped by Russia to Syria.
See also the following previous posts for further information:
Facility containing disused stores of sarin and mustard gas overrun by jihadist group
The jihadist group bringing terror to Iraq overran a Saddam Hussein chemical weapons complex on Thursday, gaining access to disused stores of hundreds of tonnes of potentially deadly poisons including mustard gas and sarin.
The facility was notorious in the 1980s and 1990s as the locus of Saddam’s industrial scale efforts to develop a chemical weapons development programme.
Isis has shown ambitions to seize and use chemical weapons in Syria leading experts to warn last night that the group could turn to improvised weapons to carry out a deadly attack in Iraq.
Hamish de Bretton-Gordon, a former commander of Britain’s chemical weapons regiment, said that al-Muthanna has large stores of weaponized and bulk mustard gas and sarin, most of which has been put beyond ready use in concrete stores.
“We remain concerned about the seizure of any military site by the [Isis],” Jen Psaki, the State Department spokeswoman, said. “We do not believe that the complex contains CW materials of military value and it would be very difficult, if not impossible, to safely move the materials.”
During its peak in the late 1980s to early 1990s, Iraq produced bunkers full of chemical munitions.
A CIA report on the facility said that 150 tons of mustard were produced each year at the peak from 1983 and pilot-scale production of Sarin began in 1984.
Full article: Isis storms Saddam-era chemical weapons complex in Iraq (The Telegraph)