WEST BRIGHTON, Staten Island — A 19-year-old man is facing serious criminal charges after allegedly stabbing his 45-year-old stepfather to death inside their Staten Island home on Monday afternoon.

According to the New York City Police Department, Damien Hurstel, 19, has been charged with murder and criminal possession of a weapon in connection with the killing of Anthony Casalaspro, 45, his stepfather.

Police responded to a 911 call reporting a stabbing at 380 Cary Avenue in the West Brighton neighborhood shortly before 4:30 p.m.

Upon arrival, officers discovered Casalaspro unresponsive in the bathtub with multiple stab wounds to his head and neck. He was pronounced dead at the scene.

Investigators say Hurstel’s sister arrived at the residence around 4:00 p.m. and found blood throughout several rooms before discovering her stepfather’s body in the bathroom. She immediately alerted authorities.

Police sources described the scene as extremely violent, confirming that the victim had sustained severe injuries and that the weapon — a knife — was recovered at the scene.

Hurstel was taken into custody without incident shortly after police arrived. Authorities have not yet disclosed a motive, but investigators are exploring the possibility that the suspect may have a history of mental illness.

Neighbors expressed shock and disbelief at the gruesome nature of the crime.

“This whole world is upside down,” said one longtime resident. “It’s terrible — you don’t do this to another person, not even to an animal.”

Another neighbor, Hugh Nembhard, who has lived across the street for six decades, said the neighborhood has changed in recent years. “I saw the father, but never the stepson,” Nembhard said. “This is a complete shock to me.”

The NYPD’s Homicide Division is leading the investigation.

Authorities continue to process evidence and interview witnesses to determine what led to the fatal stabbing.

The investigation remains active and ongoing.