AURORA, Colo. -- A Colorado dentist has been arrested in connection with the "complex and calculated" poisoning death of his wife, local police said on Sunday, ABC News reported.
The Aurora Police Department said James Toliver Craig, 45, was arrested on a charge of first-degree murder early Sunday morning.
Craig and his wife, Angela, who was suffering from "severe headaches and dizziness," arrived at a local hospital at about 8:45 p.m. on Wednesday night, officials said.
She was placed on a ventilator after her "condition deteriorated rapidly," police said in a statement, adding, "She was declared medically brain dead a short time later."
An investigation into her "sudden" death showed she'd been poisoned, said Mark Hildebrand, a division chief with the department.
"It was quickly discovered this was in fact a heinous, complex and calculated murder," Hildebrand said in a statement.
A colleague had recently opened a package addressed to Craig at the dentist's office containing potassium cyanide. He alerted a nurse at the hospital of his suspicions, leading investigators to Craig.
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Police said Craig allegedly purchased arsenic and cyanide and secretly dosed Angela in protein shakes.
The arrest affidavit showed text messages between Craig and his wife the week before her death, with Angela complaining that "my head feels funny and dizzy," even writing, "I feel drugged."
According to the affidavit, investigators found that Craig had conducted numerous online searches about poisons, including, "how many grams of pure arsenic will kill a human?" and "is arsenic detectable in autopsy?"
The couple has six children together. Family and friends told police they were struggling financially, and that Craig not only had multiple affairs, but that he had previously tried to poison her. Craig has not entered a plea yet.
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