Calif. Dad Stabs 9-Year-Old Son to Death — Then Won’t Drop Knife When Cops Show Up

A 48-year-old California father allegedly stabbed his 9-year-old son to death in a San Jose park and then charged at responding police with a knife before being fatally shot, officials say.

According to San Jose police, Mateusz Dzierbun of Fremont called 911 around 3:30 p.m. Saturday, claiming someone else had stabbed his child. He even gave a description of the suspect — a description that matched himself.

“These officers had no idea that the frantic person on the line was in fact the suspect himself,” San Jose Police Chief Paul Joseph said at a Monday press conference, per the outlets. “A deranged man who had murdered his own son.”

When officers arrived at Cataldi Park, they found Dzierbun crouched over his son’s body holding a blood-covered kitchen knife and refusing to drop it, per reporting by Fox 4, KQED and KTVU. 

Dzierbun ignored repeated pleas to drop his weapon and made several statements saying he intended to be shot, Joseph said. Then, he allegedly charged with the knife raised. 

The 9-year-old was “clearly deceased” when officers rushed to his aid. 

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“The child suffered from injuries so severe that it’s unimaginable they could have been inflicted by his own father,” Joseph said. “Been a police officer for 33 years, I don’t ever remember a parent murdering their child so brutally.”

“His call for help was actually a twisted plan to force officers to shoot him,” Joseph said. “It was a final, desperate and selfish act — suicide by cop.”

The Santa Clara County District Attorney’s Office is reviewing the shooting, including body camera footage, as part of its investigation.

Police say Dzierbun had no known criminal record or documented mental health issues. Joseph said he “moved around the country quite a bit, so homicide detectives are trying to work to retrace his steps” before Saturday.  

San Jose Mayor Matt Mahan called the incident “horrific and heartbreaking,” saying in a statement, “I cannot imagine how scared this child must have been when the person meant to be their protector became their attacker.”