The top US diplomat told reporters he could not confirm the reports, but said the United States took all such "allegations very seriously."
The Washington Post reported today that 11 Iraqi police offices had been rushed to a hospital some 80 kilometres north of Baghdad last month suffering from dizziness, vomiting and shortage of breath.
They were diagnosed as having been the victims of a poisoned gas attack allegedly unleashed by militants from the Islamic State group.
"No, I am not in a position to confirm" the report, Kerry told reporters after meeting with his South Korean counterpart Yun Byung-se.
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"We are seeking additional information in order to be able to determine whether or not we can confirm it," he added.
"The use of any chemical weapons is an abhorrent act, it's against international law, and these recent allegations underscore the importance of the work that we are currently engaged in."
But the top US diplomat stressed the reports would not change the US strategy as it builds a coalition to fight IS militants who have seized control of a large area of Iraq and Syria.