FREDERICK, Md. (AP) — An Army Corps of Engineers official says the military may have used more Agent Orange chemicals decades ago at Fort Detrick than previously reported.

Randal Curtis said Wednesday that his office has been searching government documents that indicate 20 to 30 pounds of the defoliating compounds may have been sprayed on test plots at the Army installation in Frederick from 1944 to 1968.

The Army recently pegged the amount at 17 pounds based on a preliminary search.

The Army is trying to counter claims by an activist group that its carelessness with chemicals caused a cancer cluster among neighboring residents. Public health officials haven’t found higher rates of cancer near Fort Detrick than in the rest of Frederick County.

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