Derek Fierro, a 25-year-old fourth-grade teacher, called police Friday and told them he became angry and beat his dog to death at his home, the Chicago Sun-Times reported.
When officers arrived, Fierro gave them the keys to his car, where they found the dog, a medium-sized, blonde lab-chow mix named Doc, "clearly deceased" in the trunk, court documents state.
"I got home and he had eaten through every piece of paper," Fierro told officers, a police report said. "He [defecated on] himself, so I put him in a tub. I was gonna give him a bath, and he didn't want to get in the bath and I got mad."
Fierro then began crying and told officers, "Why did I do this? I'm an animal," the police report said.
Doc was adopted from the Chicago Canine Rescue Foundation after he was removed from an abusive home, the Sun-Times said.
"It's so unfortunate how this ended up," Lisa Klotnia of the pet rescue organization said. "This guy could have called us at any time to help him out."
On Saturday, Cook County Associate Judge Donald D. Panarese Jr. ordered Fierro held in lieu of $200,000 bail and not to possess or have contact with any animals after he posts bail.
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