A 32-year-old Portland woman pleaded guilty Tuesday in U.S. District Court to health care fraud and attempting to acquire oxycodone pills by deception.

From May 2015 until March 2016, Shannon Bragdon stole blank prescriptions from the dentist office where she worked and used dozens of them to pass fraudulent prescription orders at at least nine pharmacies in southern Maine, said U.S. Attorney Thomas Delahanty in a press release.

Bragdon was caught by authorities on March 21, when a pharmacist suspected that the prescription Bragdon had presented was fake and called police. Agents from the U.S. Drug Enforcement Administration found Bragdon in the waiting area of the pharmacy and arrested her.

She faces as much as four years in prison on the drug charge and 10 years on the fraud charge, and up to $250,000 in fines for each. Her sentencing will be completed following a pre-sentencing investigation.