BERLIN (AP) — Police in Germany have arrested a midwife on suspicion of attempted murder, alleging that she administered a blood thinner to women undergoing cesarean sections.

Munich police said Thursday that a hospital in the city alerted prosecutors after bleeding during four C-sections between April and June aroused staff’s suspicions. An internal investigation by the hospital concluded that the women had been given high doses of heparin, which is used to prevent blood clots, although it wasn’t medically necessary.

Police say that the drug caused life-threatening blood loss that was stemmed by “immediate emergency measures.”

They say that the 33-year-old German midwife, who was arrested last Friday and is in detention pending formal charges, denies the allegations. Her name was not released.

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