BALTIMORE (AP) — A once-common farm pesticide may be to blame for dozens of bald eagles poisoned over the past three years in Maryland and Delaware.

The Baltimore Sun reports that U.S. Fish and Wildlife Service data show pesticides were a suspected or confirmed factor in about 50 deaths of the national bird between 2008 and 2017.

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There have been about two dozen bald eagles poisoned to death on the Delmarva Peninsula over the past three years, including at least seven in the past two months.

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Maryland Natural Resources Police Lt. Roy Rafter said the illegal chemical carbofuran killed some of the birds.

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Authorities say they think old stocks of the pesticide are being used to kill foxes and other farm pests, but it harms the eagles that scavenge the dead animal remains.