James Toliver Craig, 45, was arrested early Sunday morning by the Aurora, Colorado, police department.
CNN  — 

A Colorado dentist was arrested early Sunday morning on murder charges in the poisoning death of his wife, according to a release from the Aurora Police Department.

Aurora police detectives launched an investigation into the woman’s suspicious death, after James Toliver Craig, 45, drove his wife, 43, to a hospital around 8:45 p.m. Wednesday, because she was having “severe headaches and dizziness.” The wife’s condition deteriorated quickly after arriving at the hospital, and she was placed on a ventilator in intensive care, where she was declared medically brain-dead a short time later, police said.

Police determined the woman had been poisoned and a warrant for first-degree murder was obtained after doctors made the decision to take her off life support early Sunday morning. Craig was arrested and booked into jail around 2 a.m. Sunday, according to the release.

“When the suspicious details of this case came to light, our team of officers and homicide detectives tirelessly worked to uncover the truth behind the victim’s sudden illness and death,” Division Chief Mark Hildebrand said in the release. “It was quickly discovered this was in fact a heinous, complex and calculated murder. I am very proud of our Major Crimes Homicide Unit’s hard work in solving this case and pursuing justice for the victim.”

As of Monday morning, CNN has been unable to determine if Craig has obtained an attorney.