A Princeton, New Jersey, man accused of killing his brother and a family cat made his first court appearance Thursday.

Prosecutors charged 31-year-old Matthew Hertgen with first-degree murder in the death of his brother, 26-year-old Joseph Hertgen. He also faces third- and fourth-degree weapons charges for possessing a golf club and knife, along with animal cruelty charges for killing a cat, FOX News Digital reports.

During the virtual pretrial detention hearing in Mercer County, Assistant Deputy Public Defender Jason Matey, Assistant Prosecutor Tim McCann, and Judge Amber Gibbs rescheduled the hearing for March 6 to allow more time to gather evidence.

Police responded to a 911 call at about 11:16 p.m. on February 22, on reports of a fire and a dead body at the Michelle Mews Apartments complex in Princeton. Officers found Matthew Hertgen at the scene, identified as the caller. Inside, they discovered his brother’s body with blunt force trauma and lacerations, according to the Mercer County Prosecutor’s€™s Office.

Joseph Hertgen was pronounced dead at the scene, and autopsy results are still pending.

Mercer County authorities continue to investigate the death  and urge anyone with information to contact Sgt. Will Jett at 609-331-5010 or Det. Karl Johnson at 609-439-5258.

Officials have not yet provided a motive. Check back for updates.

[Feature Photo: Matthew and Joseph Hergen/ University of Michigan; Wesleyan University ]