U.S. Sees Possible Pattern in ISIS Chemical Attacks

Mustard agent believed used against Kurdish forces in Syria two weeks ago, before Iraq.

U.S. intelligence agencies have evidence indicating Islamic State used mustard agent against Kurdish forces for the first time at least two weeks ago in fighting in Syria, a tactic that the group may have repeated in two subsequent attacks in Iraq, U.S. officials said Friday.

The developments are fueling concerns that Islamic State has acquired a crude arsenal of banned chemicals that could herald a significant escalation of fighting in the region.

“It could be a pattern,” said a senior U.S. official briefed on the intelligence.

U.S. intelligence agencies have long believed that Islamic State aspired to obtain chemical weapons but officials said it was premature to connect the three attacks because the agents involved in the Iraq incidents were still being analyzed.

The agencies confirmed through tests that mustard agent was used in northern Syria in late July, according to officials, making it the first known attack by Islamic State using banned chemicals.

U.S. intelligence agencies suspect Islamic State likely used blister agents in at least two subsequent attacks against the Kurds in northern Iraq, on Tuesday and Thursday.

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