A Harlem man was convicted on charges he brutally abused and beat his ex-girlfriend's six-year-old son to death in 2016, the Manhattan District Attorney Cy Vance's office announced on Wednesday.

Rysheim Smith, 45, was found guilty of second-degree murder, first- and second-degree manslaughter, and endangering the welfare of a child by a New York Supreme Court jury. He was also found guilty of endangering the welfare of another child in August 2015 "by causing an incident that left the child unattended."

The NYC Medical Examiner determined that the child, Zymere Perkins, suffered from fatal child abuse syndrome. "This cause of death means that the child had evidence of acute and chronic abuse and neglect that ultimately led to his death," Julie Bolcer, a spokeswoman for the city Medical Examiner, said after the autopsy results were released.

Smith beat Zymere to death with a broken broomstick in Zymere's mother's Harlem apartment in September 2016. After Smith left the apartment, Zymere's mother, Geraldine Perkins, said she laid the child on a bed for several hours, thinking he was asleep. She eventually took him to Mount Sinai St. Luke's Hospital, where he was pronounced dead.

Perkins, 29, pleaded guilty to manslaughter and agreed to testify against Smith in exchange for reduced jail time of two-to-six years.

Despite years of evidence of abuse, Zymere was failed by the city's social services, as the New York Times reported in a detailed, graphic article yesterday. Administration for Children's Services Commissioner Gladys Carrion resigned in the wake of Zymere's and other children's deaths.

“The death of Zymere Perkins was an unthinkable tragedy that sent shockwaves through the city and inspired a reckoning with how our social services system works to protect New York’s most vulnerable,” Vance said in a release. “As proven at trial, Zymere was an innocent and helpless six-year-old boy who suffered unconscionable, ongoing violence at the hands of Rysheim Smith. Now, a Manhattan jury has rightly held the defendant accountable for this horrific murder, and I’d like to thank the members of that jury for their careful attention during this heartbreaking case.”

In 2006, Nixzmary Brown of Brooklyn was murdered by her stepfather Cesar Rodriguez, who beat her as a punishment for stealing yogurt. Both Rodriguez and the girl's mother, Nixzaliz Santiago, were acquitted of murder but convicted of manslaughter. Her death also spurred vows of reform at the ACS at the time.

Smith is scheduled to be sentenced March 27. He faces at least 15 years in prison, up to a life sentence.