Before her killing, Jennifer Schlecht worked for the United Nations Foundation, trying to improve the lives of women and girls internationally

N.Y. Man Beheads Wife, Kills Daughter, 5, in Murder-Suicide After Threats to 'Take All of Them Down'

A 42-year-old mother who worked for the United Nations Foundation as an advocate for women and girls internationally was found beheaded Wednesday night inside a Harlem apartment, where police also discovered the slain body of her 5-year-old daughter as well as the body of the girl’s father, who police say murdered his wife and daughter before killing himself.

PEOPLE spoke to multiple New York Police Department sources, who confirm Jennifer Schlecht and Abaynesh Schlecht Tedla were killed in the apartment on 121st Street by Yonathan Tedla, 46, who’d hanged himself in the couple’s bedroom.

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The sources say Schlecht was found in the apartment’s bathroom, decapitated. The little girl was located dead in a bedroom; her throat had also been slashed, according to the sources.

A motive is still being investigated.

Police responded to the apartment, finding the grisly scene, after Schlecht’s relatives asked that they perform a wellness check, an official NYPD statement explains.

Local reports indicate the couple were getting a divorce, but PEOPLE could not independently verify that information.

Tedla, sources confirm, worked for Columbia University as a computer contractor.

Schlecht was employed by the United Nations Foundation’s Family Planning 2020 project, working in international relief and development, including specialized work in reproductive health and child marriage.

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“Today, we remember our colleague, Jennifer Schlecht,” reads a statement posted to the project’s Twitter feed. “Jennifer devoted her entire career to advocating for women and girls. We will all remember her for her life — and the thousands of lives she enriched — rather than the horrible way she died.”

Beth Schlachter, Family Planning 2020’s executive director, issued a statement, saying of Schlecht: “In addition to being an adoring mother, her contribution to the lives of women and girls who are living in crisis situations has been extraordinary. That she should die under such brutal circumstances is beyond understanding … We are utterly devastated.”

Jennifer’s father, Kenneth Schlecht, told the New York Times his daughter had expressed fear for her and her child’s safety in a phone call Sunday.