A 56-year-old woman has been accused of holding her stepson, 32, captive inside their seemingly idyllic Connecticut home for two decades—during which time authorities say she subjected him to the “worst treatment of humanity” that they have ever witnessed.

Kimberly Sullivan of Waterbury, CT, was arrested on March 12 and charged with assault, kidnapping, and unlawful imprisonment. She has denied all of the allegations made against her, according to the New York Times.

Her stepson, who has not been named, was found by firefighters on Feb. 17 inside a tiny, locked bedroom on the second floor of the home after he started a fire in an apparent bid to secure his freedom.

The Waterbury Police Department revealed in a statement that Sullivan’s stepson told first responders that he had intentionally lit the fire using a lighter, hand sanitizer, and paper, claiming that his stepmother had held him captive in their four-bedroom home since he was 11.

“While receiving medical care, the male victim disclosed to first responders that he had intentionally set the fire in his upstairs room, stating, ‘I wanted my freedom,’” authorities revealed. “He further alleged that he had been held captive by Sullivan since he was approximately 11 years old.”

Police then launched an “extensive investigation” into his claims and found that Sullivan had subjected her stepson to “prolonged abuse” and “inhumane treatment.” The man, who is 5-foot-9, weighed just 68 pounds when he was found.

“Detectives determined that the victim had been held in captivity for over 20 years, enduring prolonged abuse, starvation, severe neglect, and inhumane treatment,” the statement continued.

“He was found in a severely emaciated condition and had not received medical or dental care during this time. Investigators further discovered that he had been provided with only minimal amounts of food and water, which led to his extremely malnourished condition.”

The “suffering” endured by the victim was “both heartbreaking and unimaginable,” Waterbury police chief Fernando Spagnolo said in a press conference. “In 33 years of law enforcement, this is the worst treatment of humanity that I’ve ever witnessed.”

Spagnolo stated that the conditions inside the room in which Sullivan’s stepson was allegedly held prisoner were “worse” than those found in a “jail cell.”

“The facts of this case, quite frankly, the facts are something out of a horror movie. That’s without exaggeration,” Supervisory Assistant State’s Attorney Don Therkildsen said, according to CT Post.

The alleged victim’s uncle, Kurt Sullivan, told authorities that his nephew looked “like a Holocaust survivor” when he visited him in the hospital, adding that he had not been allowed to see the man for 20 years, according to an affidavit seen by People.

Kurt said that he and his wife had previously visited Sullivan and her family at their Waterbury home on Christmas Eve for “a few years in a row,” but claimed that they were quickly “pushed away.” He alleged that during the few visits they were able to make to the home, Sullivan would “intervene” if he tried to ask his “skinny, meek, and mild-mannered” nephew any questions.

On March 13, police revealed that officers had previously visited Sullivan’s home in 2005 after being contacted by social workers, who had been approached by the alleged victim’s school over concerns about his absence, per NBC News.

However, Spagnolo claimed that nothing had appeared strange or concerning during that visit.

“The house was clean. It was lived in. [Officers] spoke to the victim at that point in time, and there were no cause for any alarm or any conditions that existed that would have led officers to believe anything other than a normal childhood in a normal family existence,” he said.

Video footage of the home that was taken by local news outlet NBC Connecticut reveal that it was in a state of disrepair when Sullivan was arrested, with wooden boards placed across all of the top-floor windows, likely as a result of the fire that was started by the alleged victim.

A beach chair had been left abandoned in the driveway, while items of clothing are seen scattered around it, and the fence appeared to have fallen or been broken down.

On the front door, a heart-shaped sign reading “Welcome” can be seen hanging from a hook.

Property records indicate that the home was last sold for $100,000 in 1991. Sullivan and her husband are both listed as owners.

At Sullivan’s arraignment, authorities said that her stepson had been detained inside an 8-by-9-foot room since he was in the fourth grade, while the affidavit reveals that the alleged victim said he had not been allowed to leave the home since he was 14 or 15.

He further claimed that he was only let out of his room once a day, for between 15 minutes and two hours, during which time he would do chores in and around the home, before being locked back inside his room.

He said that his father, who is deceased, used to occasionally let him out of the room on weekends, when he would be allowed to do work in the yard. However, he said that after his father’s death, his stepmother’s alleged abuse worsened, claiming that he was given just two sandwiches per day and the equivalent of two bottles of water.

Per NBC News, he said that he had to construct a DIY toilet system in order to relieve himself, which involved urinating into a bottle and then using straws to dispose of the contents of the bottle through a small hole in his window.

Spagnolo added that the victim said the locks on his door “increased in security levels as time progressed,” noting that authorities found “a number of different styles of exterior locks” when they visited the property.

In a statement made by her lawyer, Ioannis Kaloidis, Sullivan vehemently denied the charges against her.

Her stepson “was not locked in a room,” Kaloidis stated. “She did not restrain him in any way. She provided food, she provided shelter. She is blown away by these allegations.”