A 22-year-old pregnant North Dakota woman found dead this week after vanishing from her apartment building earlier this month was killed in a homicide, according to preliminary autopsy results, police said.
Savanna LaFontaine-Greywind‘s body was found wrapped in plastic on Sunday afternoon in the Red River, not far outside the Fargo, North Dakota, area, just over the border in Minnesota, according to investigators.
In a statement Tuesday, Fargo police said the “preliminary cause of Savanna’s death was due to homicidal violence.”
However, the statement continued, “We are unable to release the specific details of Savanna’s death, or the manner in which Savanna’s baby was born.” Her body was sent for autopsy in St. Paul, Minnesota. A full report is not expected for weeks.
LaFontaine-Greywind, who was eight months pregnant, had been missing for nine days when her remains were found. Her family has said she was last seen on Aug. 19, at their Fargo apartment, going upstairs to help a female neighbor sew a dress.
That woman and the man she lives with, Brooke Lynn Crews, 38, and 32-year-old William Henry Hoehn, were arrested on Thursday — three days before the discovery of LaFontaine-Greywind’s body — and charged with conspiracy to commit kidnapping and conspiracy to commit murder in connection with her disappearance and death.
It was not immediately clear if Crews and Hoehn would face additional charges following the autopsy.
Police said a newborn believed to be LaFontaine-Greywind’s baby girl was allegedly found with Crews in the pair’s third-floor apartment on Thursday. Authorities had searched the residence multiple times before the discovery of the newborn, including in the immediate aftermath of LaFontaine-Greywind going missing.
“Savanna was a victim of a cruel and vicious act of depravity,” Fargo Police Department Chief David Todd said at a news conference on Monday.
Authorities have also said they were investigating a farmstead near where LaFontaine-Greywind’s body was found, at which searchers found “suspicious items” that indicate it may be a crime scene.
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No additional details as to how LaFontaine-Greywind died or gave birth have been released. The newborn, who is in “good health” remains in the custody of Cass County officials, authorities have said.
DNA testing was being conducted to confirm the child’s identity.
Hoehn and Crews allegedly gave police information that led them to believe the baby found in their apartment is LaFontaine-Greywind’s child, but they did not answer questions about the young woman’s whereabouts, Chief Todd has said.
Court documents obtained by PEOPLE show the suspects gave conflicting accounts of how they came to have the child:
Hoehn allegedly told police he arrived home from work on Aug. 19 to find Crews cleaning up blood in the bathroom. She was also holding a baby girl and allegedly told him, “This is our baby, this is our family.”
Hoehn allegedly told police he removed garbage bags containing bloody towels and his own bloody shoes and left them in a dumpster in West Fargo.
However, Crews allegedly told detectives that she had invited LaFontaine-Greywind to their apartment on Aug. 19 and taught the pregnant woman how to self-induce birth by breaking her own water. Crews claimed the other woman then left, only to return two days later to give her her newborn.
Speaking to PEOPLE following the confirmation of her daughter’s death, Norberta Greywind said she was thankful to know her granddaughter is safe.
“She’s all we have now,” Greywind said. “Knowing we have her, it gives me peace.”
LaFontaine-Greywind and her boyfriend, Ashton Matheny, were planning on moving in together in September, her mother said. Their baby was due Sept. 20 and they already had a name for her: Haisley Jo.
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“She loved everyone, she loved kids, her family — she would have been a wonderful mom,” Greywind said of her daughter.
Both Crews and Hoehn remain jailed and they have not yet entered pleas to the charges against them.
Hoehn’s attorney, Steve Mottinger, declined to comment on the charges. Crews’ attorney, Stormy Vickers, could not be reached by PEOPLE.