FRESNO (CBS/AP) — The Fresno County coroner says the woman who fatally shot three family members before killing herself was extremely high on methamphetamine.

Coroner Dr. David Hadden said people with more than 300 nanograms per milliliter of the drug in their systems tend to be at risk for bizarre behavior. Toxicology reports show that 23-year-old Aide Mendez had more than eight times that — 2,500 nanograms per milliliter—when she went on the Jan. 15 shooting rampage.

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Fresno police say Mendez killed her 3-year-old son and 17-month-old daughter, as well as her husband’s cousin, before turning the gun on herself. The husband also was shot and stabbed, but survived.

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Police say Mendez took video of herself smoking meth hours before the killings.

Hadden says the high level in her system indicates frequent, long-term use.

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