Inset: Rodolfo Gonzalez (Waupaca County Jail). Background: Apartment in New London, Wisconsin, where Gonzalez allegedly killed his mother (WLUK).

A Wisconsin man allegedly stabbed his mother to death and covered her head with cat litter before he set fire to her apartment.

Rodolfo Gonzalez, 39, stands accused of first-degree intentional homicide, recklessly endangering safety, arson, mutilating a corpse and resisting an officer.

Cops and firefighters responded on Sunday to an apartment fire in New London, which is about 40 miles west of Green Bay, according to a probable cause arrest affidavit posted by local Fox affiliate WLUK.

Firefighters found smoke coming from a fifth-floor apartment and doused three separate fires. They found an unresponsive woman suffering from several stab wounds to the neck on the bed.

A fire had been set between her legs, cops noted. There was also cat litter covering her head. She was pronounced dead.

Investigators reviewed video footage that allegedly showed Gonzalez, who lived with his mother, enter the apartment holding what appeared to be a book around the time of the fire.

He had already been facing attempted murder charges stemming from a "violent incident" involving his mother in February, cops said. WLUK reported he had been deemed incompetent to stand trial.

Officers located Gonzalez sitting on a bench near an elementary school a few hours later and tried to take him into custody. He allegedly resisted arrest and had to be subdued in leg shackles. Cops found two lighters and a Bible on him.

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An autopsy determined the victim died from multiple sharp force injuries to the neck. She was already dead when her son set fire to the apartment, as there was no soot in her lungs or CO2 in her blood, detectives wrote. The affidavit did not detail a motive for the crime nor did it identify the victim.

Gonzalez remains at the Waupaca County Jail on a $1 million bond. His next court date is set for Aug. 4.