The United States military has acknowledged that American soldiers found thousands of abandoned chemical weapons in Iraq and that hundreds of troops notified medical personnel they had been exposed to them.

Those exposures, which were disclosures only after an investigation by The New York Times,
have left some soldiers sickened, likely as a result of handling leaking barrels. But a new report in The Times suggests Army officials did not come clean about the exposures, instead suggesting a variety of other potential causes for those ailments, including sarin gas and pesticides.

Thomas S. Blanton, director of the National Security Archive, which advocates open government, condemned the government’s refusal to share its information.

“Soldiers exposed to something really dangerous cannot find out what it was because ‘Sorry it’s classified’?” he said. “It’s creepy and it’s crazy.

“The outrage here is extraordinary.”