Steven Pladl's is also accused of killing their baby and her adoptive father before allegedly killing himself.
Those deaths came after Pladl reportedly killed his 7-month-old child in a North Carolina home.
The shootings occurred roughly the same time as police in Knightdale found the infant, Bennett Pladl, dead inside the home where Steven Pladl lived.
Authorities found 7-month-old Bennett Pladl dead in a home in Wake County Thursday morning while conducting a welfare check on Earlston Court.
He called his daughter's adoptive family in New Milford on Wednesday night saying he was going to see them, police in CT said. Katie was legally adopted out of state when she was born.
"Oh God, he told me to call the police and I shouldn't go over there", a caller identified as Steven's mother told the dispatcher.
Before Katie moved into Alyssa and Steven's Henrico home, she lived in NY with her adoptive parents, Kelly and Anthony Fusco.
The couple were arrested January 18 and charged with being fugitives from justice in Virginia, where they were wanted on charges of incest with an adult, adultery and contributing to delinquency.
The murder-suicide by Steven Pladl spanned three states, authorities told local media. Officials said Steven Pladl used an "assault-type weapon" similar to an AR-15.
"And he. he said he killed his wife, he killed her father. I didn't ask him, I didn't want to know", she said. "He told me to call the police and I shouldn't go over there".
A man who had an incestuous relationship with his daughter and fathered a child with her shot and killed her and her adoptive father in a pickup truck Thursday and then killed himself, police said.
Knightdale Police Chief Lawrence Capps confirmed in a press release the infant's death is linked to the shootings in ct and ny and that Katie and Steven Pladl were involved. When Katie Pladl turned 18, she made contact with her biological parents, staying with them, and entered into a sexual relationship with her own father, which later produced a child. Steven left his wife to marry his daughter. Pladl didn't give any indication he would harm anyone, Friedman said.
Beetge said the baby has been handed back to the 35-year-old mother and their case is being overseen by local social services to ensure the child is in a place of safety.
The caller then said Steven admitted to killing his wife and her adoptive father, the station reports. Police then found Steven, who was 43 or 44, in a minivan in NY on Thursday. Over the course of the day, Steven Pladl was also located, Capps said.
Capps said it was his understanding Steven Pladl drove to the NY area "for the specific goal of making some confrontations". Unfortunately, they are not uncommon in society.