Italian police are investigating a nurse -- who was arrested over the weekend for a patient’s death -- and who prosecutors believe may have killed 37 others because they or their relatives annoyed her.

Daniela Poggiali, 42, a nurse at Umberto I Hospital in Lugo, was initially charged with murder over the death of Rosa Calderoni, 78, who was found dead in April with high levels of potassium in her bloodstream, according to Sky News.

Authorities are now reviewing 37 other cases, 10 of which they describe as “very suspicious.” Prosecutors believe Poggiali killed additional patients who bothered her or had demanding relatives.

Pictures reportedly found on Poggiali’s phone showed her giving a thumbs up next to a dead patient, Sky News reports.

Poggiali – when questioned by prosecutors -- denied wrongdoing in the deaths, claiming that she is a victim of a conspiracy organized by her enemies, the ANSA news agency reports.

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