Naomi Elkins, 27, of Lakewood Township, was arrested on Tuesday after admitting to killing her 1-year-old and 3-year-old children.
According to a criminal complaint, Elkins told investigators that she started having "concerning thoughts" on May 24 while her husband left for a business trip to Virginia. Elkins says she dropped her kids off at daycare and spent the night praying.
Authorities say she followed a similar routine on Tuesday by taking her children to daycare. After picking them up, she told police "she believed that she needed to kill the children."
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When officers arrived at the home on Shenandoah Drive around 4:50 p.m., a serrated knife with a red handle was found in the sink and two bathtubs were filled with water.
Investigators say she stabbed her 1-year-old and then drowned both children. Emergency responders tried to perform life-saving efforts on both kids but were unsuccessful.
After drowning both daughters, she claims she realized she had done something wrong and called emergency responders.
During an interview with police, she allegedly said that she knew that it was illegal to kill her children and that what she did was wrong.
Neighbors, many of whom are members of the Orthodox Jewish community, say the family moved in a few months ago.
Elkins is being held in the Ocean County Jail. She has a detention hearing scheduled for Monday in Ocean County Superior Court.