This quotation by Killer Kane comes in Chapter 20 of Freak the Mighty. Killer has kidnapped his son, Max, in the hopes that he will be able to take Max with him on his new adventure: He plans to pretend to be "a man of God" and make lots of money from the people he cons into giving him money. But when Loretta attempts to free Max, Killer catches her and begins to strangle her. When Max tries to protect her, he cries out that he witnessed his father strangle his own mother. Killer doesn't believe it at first, but Max convinces his father that he saw the murder. When Max recites the whole chain of events, including the color of the clothing his father was wearing, Killer realizes that his son is telling the truth. Max is a witness that his father cannot allow to run free, so he decides he must also kill Max.
"I have to clean this up and get out of here."
That's when his hands start to tighten hard around my neck...
He squeezes and squeezes and squeezes.
Killer Kane, who strangled his wife before Max's eyes, would have done the same to his son, except for the intervention of Freak with his squirt gun.