Princeton Man Accused of Murdering Brother and Cat in Apartment Tragedy

Princeton, N.J. — A 31-year-old man is facing murder charges after allegedly killing his younger brother and their family cat in their shared apartment on February 22. Matthew Hertgen reportedly used a knife and a golf club in the brutal attack against 26-year-old Joseph Hertgen.

According to a probable cause statement obtained by Fox News Digital, Matthew had been suffering from severe mental illness for the past five years. Before the attack, he spent several hours with Joseph, during which time he exhibited disturbing behavior, including terrifying visions.

Matthew’s surviving brother, who remains unnamed, picked him up around 4:30 p.m. and took him to the grocery store before returning to his residence for several hours. At approximately 10:00 p.m., the surviving brother departed, leaving Matthew with Joseph.

Just an hour before the incident, the surviving brother sent a text message to Joseph, advising him of Matthew’s struggles. Joseph responded affirmatively, indicating his willingness to help. The message exchange continued with the surviving brother inviting Joseph to go on a hike the next day, showing support for his sibling.

Police were dispatched to the scene shortly after Matthew called 911 around 11:16 p.m. to report a fire and to alert them of Joseph’s body. When they arrived, they discovered Matthew, who appeared disoriented, as well as his brother’s body showing significant head injury, including a missing eye, and wounds to the chest.

Matthew reportedly told the dispatcher that he would not provide more details about how Joseph was injured. Investigators also found gruesome evidence at the scene: blood-smeared utensils and a partially burned cat on an ottoman.

During an interview with law enforcement, Matthew reportedly stated, “I went into a fit of madness… maybe like forty minutes ago,” indicating a lack of control over his actions during the attack.

Hertgen’s detention hearing took place on March 6, but no evidence was presented as he consented to pretrial detention, which removes the need for immediate evidence to justify holding him. Family members were notably absent from the proceedings, and Hertgen is scheduled to return to court on March 24.

Joseph Hertgen was pronounced dead at the scene, and an autopsy is pending as local officials continue to investigate the circumstances surrounding his death as a homicide. The Hertgen brothers were known as talented soccer players during their time at Toms River High School, with Joseph having been recruited to play at the University of Michigan, while Matthew attended Wesleyan University in Connecticut.