(NEW HAMPSHIRE UNION LEADER) — A Dover grandmother infected with hepatitis C filed suit against Exeter Hospital Tuesday as the U.S. Attorney’s Office announced it has joined the criminal probe into the outbreak of the virus linked to the hospital’s cardiac catheterization laboratory.

U.S. Attorney for New Hampshire John P. Kacavas said his office is assisting state and local officials because of the authority granted it under the anti-tampering law passed by Congress in 1982 following the so-called Chicago Tylenol murders.

“We have the authority to prosecute a person or persons who may be criminally responsible for tampering,” Kacavas said. “The investigation will go where the facts lead us but — if it leads to a tampering issue — then we have an investigation directly on point.”

State health officials last week said a hospital employee who used syringes to inject painkillers intended for patients is the most likely source of the outbreak of the potentially deadly virus that to date has infected 19 former patients.

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