The stabbing happened in December 2022 as a 15-year-old girl took her dog Bebe for a walk in the 6600-block of West Irving Park Road.
She managed to fight off the attacker and run, but not before Bebe suffered serious, life-threatening injuries. The building's security cameras captured the attack.
Police arrested and charged Jeannette Olivo, 61 at the time, in the attack.
The video in the player above is from a previous report.
RELATED | Woman, 61, stabs dog being walked by teen girl on Chicago's NW Side, police say
She was charged with two felony counts of aggravated cruelty to animals and aggravated assault with a deadly weapon.
On Wednesday, after a one-day bench trial, Olivo was found not guilty by reason of insanity.
She was remanded to the Department of Human Services for further evaluation.
Meanwhile, Bebe the chihuahua survived a life-saving surgery. He was taken home a couple of days after the attack.
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