Italian nurse Daniela Poggiali was arrested last weekend for allegedly killing up to 38 patients because she found them and their relatives "annoying," according to reports.
After arresting Poggiali in the northern Italian town of Lugo, police reportedly found a selfie of the 42-year-old nurse giving a thumbs-up with a recently deceased patient.
According to local newspaper Corriere della Sera, Poggiali was arrested on suspicion of poisoning a 78-year-old patient, Rosa Calderoni, died from an injection of potassium chloride.
Police told reporters that they are widening their investigation to include other "very suspicious" deaths that happened under Poggiali's watch.
Co-workers allegedly described Poggiali as a "cold, polished" person, and suspected her of misconduct because patients would suddenly die under her care.
Speaking to Corriere della Sera, her co-workers said they believed she would often sedate patients if she found them bothersome during her shift.
One co-worker reportedly said, "We wondered whether these deaths could be so frequent without anyone doing anything."