MADISON, Ill. — Madison Police confirmed a man was arrested and taken into custody Monday afternoon after a dog was dropped off at the Madison Police Department late last week suffering severe acid burns.

"It's unjust; it's heinous," Detective Kyle Graham said. 

Deb White, president of Pound Pets Rescue Inc., received a Facebook message Thursday saying someone had poured a chemical on the dog and dropped it off at the department. She picked the dog up and took it to get medical treatment. 

"Some of his skin is gone all the way down to his tendons," White said. "It's a good possibility that he will lose his eye"

White also said the acid burns were so bad in some places, the dog will have to have his genitals removed. 

Graham said after interviewing a person of interest Monday, he believes they have the person responsible. He could not give a name or a mugshot because formal charges have not been filed, but he described the suspect as a 45-year-old man. 

He also said he believes the suspect acted out of anger. 

"If someone can do this to a small dog and then you think about they can do to a person, out in the public," Graham said. "We don't want those types of people walking around.

Graham said he expects charges to be filed Tuesday afternoon.

In the meantime, White and her team are focused on Charlie's recovery. 

"This is probably the worst we've seen," White said. "The second is Belle."

Pound Pets worked with Belle late last year after she was found malnourished and ridden with fleas.

RELATED: She's surviving one of the worst cases of abuse this shelter's ever seen

"She was given a 10 percent chance of survival," White said. "She's 70 pounds now and living the life. A beautiful girl."

Kathy Mayes, who also works with Pound Pets, said Charlie still trusts humans.

"We spend time with every day holding him and letting him know we're there for him," Mayes said. "He just wants to snuggle. He wants that affirmation. He's eating and drinking.  He wants to survive."

The women said doctors gave Charlie a 50-50 chance of survival. However, they said they believe he will pull through. They're planning to make shirts to support Charlie, touting the slogan "Charlie's  Angels".

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