A Mesa man came home from work Monday afternoon and found his wife and 12-year-old daughter dead, according to police.
A police spokesman says the circumstances of their deaths suggest a murder/suicide.
According to police, 45-year-old Marcia Wentzel and 12-year-old Caitlin Wentzel were both suffering from "debilitating, long-term medical conditions."
Inside the home, near Power Road and McKellips Road, police found two suicide notes.
Police didn't give a detailed description of the scene but said it suggests that asphyxiation and prescription drug overdose may have contributed to their deaths, although the medical examiner hasn't made a determination at this point.
"We have no one in custody and no information indicating anyone else is involved," Mesa Police Sergeant Tony Landato says.
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