The Princeton, New Jersey, man known as a star student in high school who is now accused of killing his brother and a family cat allegedly told police he had a “fit of madness” when they responded to the scene of the crime, according to court records obtained by local news outlets.

Matthew Hertgen, 31, is accused of murdering his 26-year-old brother, Joseph Hertgen, in the family’s Princeton apartment, allegedly with a knife and golf club. He is also charged with animal cruelty related to the death of a cat.

Princeton police initially responded to a 911 call from Matthew on Feb. 22 around 11:16 p.m. reporting a fire and his brother’s dead body at the Michelle Mews Apartments complex.

When a dispatcher asked Matthew how his brother was injured, he said, “I’m not gonna go into any more details right now,” a probable cause statement obtained by NJ.com reads.

Joseph and Matthew Hertgen were star soccer players in high school and college. They were both athletes at Toms River High School, and Matthew went on to study at Wesleyan University in Connecticut. Joseph Hertgen was recruited to play soccer at the University of Michigan.