The Sierra County Sheriff's Office in New Mexico says a yearlong investigation has led to the arrest of a registered nurse accused of using prescription drugs to kill her fiance.

Kandi Adams was arrested in Nevada on charges of murder, tampering with evidence and forgery last week and has since been extradited to New Mexico.

Undersheriff Dave Elston said the investigation began on March 20, 2015, after Adams called 911 to report that her fiance was not breathing. Deputies found that the fiance, Richard Harris, had been dead for several hours.

Elston said Adams cashed a $5,000 forged check and made a fake will saying she was to inherit Harris' belongings.

A toxicology report found Harris had been given prescription opioid painkillers and a sedative.

Adams was living in Ely, Nevada, when arrested. Court records do not have an attorney listed for her.