MADISON, Wis. -

A former University of Wisconsin Hospital nurse is facing 42 felony charges related to allegations that she stole painkiller medications, according to a release from UW police.

Police said they were contacted March 13 about a hospital investigation of a nurse. Police investigators said Stefanie A. Jones, 31, of Cottage Grove, had been diverting drugs from patients in at least 42 different cases.

Jones took morphine syringes from a secured machine and replaced them with syringes that contained water or another unknown liquid, according to investigators. A pharmacy technician noticed that red tamper-evidence caps on the drug syringes had been tampered with.

Police said Jones admitted to taking the pain killers and taking them for herself. She said she had been doing so since October 2013.

Police don’t know how many patients were affected by her actions.

Investigators said Jones recklessly endangered human life by replacing the drugs with water or an unknown liquid.

Jones was arrested Thursday on suspicion of 42 felony counts of diversion of drugs and 42 counts of reckless injury.