Senior U.S. intelligence officials confirmed Tuesday that the Islamic State has been successful in developing and deploying chemical weapons in Iraq and Syria, naming it the first attack of its kind in more than two decades.
Confirmation that the group used mustard gas came during National Intelligence Director James Clapper's testimony before the Senate Armed Services Committee, Fox News reported.
It is not known exactly where and when the chemical weapons were deployed, but sufficient evidence has shown the extremist group was experimenting with them.
"[The Syrian government] has used chemicals against the opposition on multiple occasions since Syria joined the Chemical Weapons Convention," Clapper said. "[The Islamic State] has also used toxic chemicals in Iraq and Syria, including the blister agent Sulfur mustard."
Clapper confirmed that this is the first time a terror organization has created and utilized "chemical warfare agent" since the radical group Aum Shinrikyo used sarin in a 1995 Tokyo attack.
Photo evidence of possible chemical weaponization in northern Iraq was presented by the Kurds last summer, according to Fox News. The images reportedly showed burned and blistered skin following the exposure to "odorless, colorless" agents absorbed through clothing.
A doctor stationed in northern Iraq said he treated Kurdish fighters last year whom ISIS allegedly used as "lab rats" to test WMD. His reports showed a plethora of burns and illnesses suggesting that "mustard gas, precursors as well as neurotoxic acids" were being tested.
Evidence also revealed that Damascus has been using chemical weapons against Syrian opposition and civilians, despite two-year-old agreements do decrease its stockpile.
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