There’s been a huge twist for a cannibal killer who went on a rampage that left his brother lying in a pool of blood, minus an eyeball.

A cannibal killer – who was determined to be not guilty by reason of insanity – was found dead in his jail cell in New Jersey, US, in an apparent suicide.

Matthew Hertgen was found dead at Mercer County Jail on May 8, the Mercer County Prosecutor’s Office told local news website NJ.com, which revealed the death on Friday. An official cause of death has not been released.

He previously attempted to take his own life in his Mercer County Jail cell a week after his February 2025 arrest, the New York Post reported.

Hertgen, 31, was found not criminally responsible for his brother’s murder by reason of insanity by Mercer County Superior Court Judge Robert Lytle on March 19.

Matthew Hertgen has been found dead. Picture: wesleyan.edu
The former Wesleyan soccer player allegedly ripped out his little brother’s eyeball and devoured it after stabbing and beating him to death with golf clubs in their ritzy apartment in February 2025.

Hertgen also set the family cat on fire after his horrific slaughter of his 26-year-old brother Joseph.

Joseph’s corpse was found by cops lying in a pool of blood beside a bloody knife, after the twisted rampage, police officials said.

Surveillance footage shown at Hertgen’s trial showed him tackling Matthew to the ground and assaulting him.

Warning: Graphic

A cannibal killer – who was determined to be not guilty by reason of insanity – was found dead in his jail cell in New Jersey, US, in an apparent suicide.

Matthew Hertgen was found dead at Mercer County Jail on May 8, the Mercer County Prosecutor’s Office told local news website NJ.com, which revealed the death on Friday. An official cause of death has not been released.

He previously attempted to take his own life in his Mercer County Jail cell a week after his February 2025 arrest, the New York Post reported.

Hertgen, 31, was found not criminally responsible for his brother’s murder by reason of insanity by Mercer County Superior Court Judge Robert Lytle on March 19.

Matthew Hertgen has been found dead. Picture: wesleyan.edu
The former Wesleyan soccer player allegedly ripped out his little brother’s eyeball and devoured it after stabbing and beating him to death with golf clubs in their ritzy apartment in February 2025.

Hertgen also set the family cat on fire after his horrific slaughter of his 26-year-old brother Joseph.

Joseph’s corpse was found by cops lying in a pool of blood beside a bloody knife, after the twisted rampage, police officials said.

Surveillance footage shown at Hertgen’s trial showed him tackling Matthew to the ground and assaulting him.

Matthew Hertgen pictured in his mugshot. Picture: Mercer County prosecutor’s office

Joseph Hertgen was pronounced dead at the scene. Picture: University of Michigan
The deranged cannibal suffered from “prophetic and divine visions,” according to forensic psychologist Dr. Gianni Pirelli, and was found not guilty by reason of insanity.

Pirelli testified that Hertgen had been diagnosed with schizophrenia and that he believed himself at various times to be Jesus Christ, anti-Christ, God or to have multiple souls.

“Anytime he closes his eyes, he’s seeing tremendous visions,” Pirelli said.

He also believed that the world was on the brink of the apocalypse, and only a “sacrificial murder could save it,” the doctor testified.

He was also influenced by a chapter in Swiss psychologist Carl Jung’s Red Book entitled The Sacrificial Murder.

Matthew Hertgen has been found dead.

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“It kind of clicks for him and he puts two and two together,” Pirelli said.

Hertgen’s mental health problems began when he was living in New York City in 2021.

He had an idyllic childhood and grew up with his brothers in a $1.5 million home in Toms River before his family relocated to the luxe Michelle Mews apartments.

His family remembered the delusional maniac as a “caring and loving person” in his obituary.

“During his later years, Matthew struggled with severe and profound mental health issues; yet he expressed sorrow, remorse, and repentance in many ways,” the obituary stated.

This story originally appeared on the New York Post and was republished with permission.