NEW YORK (CBSNewYork/AP) — A new indictment Tuesday reveled new allegations against a man accused of killing his onetime high school teacher and the 4-year-old son he had with her.

Isaac Duran Infante, 23, is accused in the murder of Felicia Barahona, 36, and their son in the woman’s West Harlem apartment on Dec. 22. He is charged with first- and second-degree murder.

Manhattan District Attorney Cyrus Vance said in a news release that the new indictment in the case reveals unconscionable acts of violence against a single mother and the defendant’s own defenseless, 4-year-old son.”

Barahona was found dead Monday, Dec. 26, in her apartment on West 153rd Street with an electrical cord around her neck. Her son was found face down in the bathtub.

Police last month said Infante was in New York City from Bethlehem, Pennsylvania visiting friends and family for the holidays.

Prosecutors alleged Monday that around 9:15 p.m. Dec. 22, Infante wrapped an electrical cord around Barahona’s neck, and then squeezed the cord so tightly that she choked to death.

After witnessing his mother being strangled, Miguel Barahona, 4, was crying in the bathroom when the suspect took a computer cable, tied it around his neck, and also strangled him, prosecutors alleged.

Infante then lay the boy’s body face down in the bathtub under several inches of water, prosecutors alleged.

Infante then put on Felicia Barahona’s clothing and left the building while concealing his face, prosecutors said. He then went to back to Bethlehem, Pennsylvania where he discarded the clothing, prosecutors said.

Infante was arrested on Dec. 27.

Police last month said during a confession at the 30th Precinct, Infante admitted he and his ex-lover “got into an argument” and “he knocked her to the ground in the living room of her third floor apartment.”

He allegedly told police she was holding a pair of scissors when she got up. At that point he grabbed a phone cord and strangled her, police said last month.

Police said last month that during his confession, Infante admitted he didn’t like how Felicia was raising the child — things like feeding Miguel a lot of fast food and dressing him in feminine looking clothing. Also, he claimed that Barahona was interfering with his relationship with his new girlfriend.

A 2012 report by school investigators determined the 36-year-old Barahona began a sexual relationship with Duran Infante when he turned 18.

The report found Barahona believed she and Infante would get married before their relationship ended. Barahona was fired as a New York City public school teacher, but she was never arrested for that relationship.

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