O’FALLON, Mo. (AP) – A key figure in a previous murder case is now charged with killing a man she claimed was an intruder.

Pamela Hupp of O’Fallon, Missouri, was arrested Tuesday and charged with first-degree murder. Police say she is hospitalized in stable condition after repeatedly stabbing herself with a pen in a women’s restroom while in custody. Bond is set at $2 million.

Hupp fatally shot Louis Gumpenberger Aug. 16. She told police Gumpenberger was a stranger who confronted her on her driveway then followed her into the home.

But St. Charles County prosecutor Tim Lohmar says Hupp set up Gumpenberger and killed him without provocation.

Hupp was a witness against Russell Faria, convicted of fatally stabbing his wife, Betsy Faria, near Troy in 2011.

The conviction was reversed and Faria was acquitted in 2015, partly on claims that he should have been able to argue in the first trial that Hupp had motive to kill Betsy Faria.