Police say Ian Michael Nielsen made his way into the victim's home around 6 a.m. and began searching for money.
At some point during the incident, the victim was thrown into the trunk of her car and bound with duct tape and zip ties. The suspect then drove around to several different parts of the city.
Hugh Lockerby, with the Scottsdale Police Violent Crimes Unit, said Nielsen was arrested Tuesday morning, and admitted to the robbery and kidnapping. Police say witness accounts and forensics evidence was used to link Nielsen to the crime.
Nielsen expressed remorse, and said he did it for drugs and money, police say.
Lockerby said the woman was able to free herself from the trunk of the car around 1:30 p.m. after several hours that day and discovered the vehicle had been left in the parking lot of Scottsdale Fashion Square mall.
Witnesses who saw the elderly woman contacted 911, and she was taken to a nearby hospital for treatment.
She suffered extensive injuries including a broken sternum, and was treated at the hospital for several days before being released.
Nielsen is charged with Attempted 2nd Degree Murder, Kidnapping, Robbery, and Aggravated Assault.
A judge set his secured bond at $1 million.
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