In the calls, released by North Carolina police, the woman says her son, Steven Pladl, had killed the baby in Knightdale, North Carolina, then killed his daughter and her adoptive father in New Milford, Connecticut. Authorities say he then drove over the border to New York and committed suicide.
"He told me he ... oh God ... he told me killed his baby and he's in the house," the woman cried.
The boy, Bennett Pladl, was born from an incestuous relationship between Pladl and his daughter, 20-year-old Katie Pladl, who was also his wife. The mother said in the 911 call that Pladl told her his wife had broken up with him over the phone.
"His wife broke up with him over the phone yesterday, and he just ... he killed his wife, he killed her father ... I can't even believe this is happening," she said, sobbing.
Listen to the whole 911 call
Connecticut police said in a news conference Friday morning that Steven Pladl used an AR-15 to kill Katie Pladl and her adoptive father, 56-year-old Anthony Busco.
New Milford Police Chief Shawn Boyne said Steven pulled up next to a car occupied by Anthony and Katie and fired multiple shots into their upper torso and head areas.
The 911 call revealed gruesome details surrounding the murder-suicide case involving the incestuous couple who were charged earlier this year after having a baby together.
After police received the call Thursday, Knightdale officers found Bennett Pladl dead in a home on Earlston Court. Later in the morning, police in Connecticut found two people fatally shot inside a pickup truck in New Milford.
Officials say Katie Pladl was born in January 1998 to Steven Pladl and her mother and then legally adopted out of state. According to warrants, she used social media to reach out to her biological parents after she turned 18, and in August of 2016, she moved in with her biological parents and their two other children.
Steven Pladl eventually left his wife to be with Katie, warrants say. The wife told authorities that when she moved out of the home, Steven had been sleeping on the floor of Katie's bedroom.
The wife also said that she learned her daughter was pregnant and that Steven was the father in May 2017, after reading one of her other children's journal. She said that she contacted Steven, and he admitted that Katie was pregnant with his child and that the two had plans to get married. Warrants said the two young children were told by Steven to refer to Katie as stepmom, even though she's actually their sister.
They moved to Wake County, North Carolina, at some point after May 31, 2017. Warrants say their child was born in September 2017.
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