ATLANTA (AP) -- The federal government says today that more than one thousand people died over two years from an illegal version of the painkiller fentanyl.

Health officials say the spike of overdoses seems to have ended, and they are pointing to law enforcement's shutdown of a fentanyl operation in Mexico in 2006.

The wave of fentanyl overdoses first came to light in Chicago in 2005, and by 2006 more clusters were identified in Philadelphia, Detroit and other cities.

Fentanyl is a prescription painkiller, often prescribed for cancer patients and administered through a patch. But it also is a powerful, euphoria-inducing narcotic, 30 to 50 times more potent than heroin.

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