Authorities allege David Kwiatkowsi, 33, injected himself with syringes of fentanyl, a powerful painkiller, that he stole from patients who were scheduled for surgery. He then filled the syringes with saline and replaced them for use in the medical procedure. "Instead of receiving the prescribed dose of fentanyl, patients instead received saline tained by Kwiatkowski's infected blood," federal prosecutors said.

Kwiatkwoski was indicted last month by a federal grand jury in New Hampshire on fraud and product-tampering charges.

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