The scene left officers traumatised (Image: Getty Images/iStockphoto)

When the emergency dispatcher answered Dena Schlosser’s call, nothing in her composed demeanor or steady voice suggested the horrific tragedy that had just unfolded.

Asked if there was an emergency, she displayed no signs of distress or agitation, speaking so softly that a hymn playing gently in the background was audible during the 2004 call.

When the 911 operator inquired why she was calling and what had occurred with her baby, Schlosser’s response was chillingly direct: “Yes. I cut her arms off.”

Officers raced to an apartment in Plano, Texas, where they encountered a scene so harrowing it would haunt investigators for years.

Schlosser sat calmly in the living room, drenched in blood from head to toe. Close by, her infant daughter lay in a crib, grievously wounded.

The woman sounded calm on the 911 call (Image: Getty Images)

The child was taken to hospital but tragically succumbed to her injuries shortly after arrival. Schlosser had used a knife to sever both of her 11-month-old daughter’s arms before turning on herself.

Remarkably, she had survived a self-inflicted gunshot wound to the head. As officers secured the scene, Christian music played on.

Those present would later describe Schlosser as disturbingly serene, even humming hymns as she was placed under arrest.

What made the incident even more difficult to fathom was how ordinary everything had appeared beforehand. Neighbors portrayed Schlosser as appearing caring and loving. She regularly walked her infant through the area most afternoons, took her kids to the pool, and often paused for friendly chats with people she encountered.

“There were never any red flags,” one neighbor said. “She looked like a great mum”, reports the Mirror.

Police could not save the baby (Image: Getty Images/iStockphoto)

However, in private, the situation had been deteriorating.

Months prior, Schlosser had experienced a serious psychotic episode after giving birth and received a diagnosis of postpartum mental illness.

Child welfare authorities had examined the household following her admission to hospital, but the investigation was subsequently discontinued when she demonstrated stability and adherence to her treatment plan.

On the day of the tragedy, something in Schlosser’s mind clearly malfunctioned catastrophically.

Mental health professionals subsequently testified Schlosser believed she was receiving direct instructions from God, becoming convinced her baby was part of a divine plan connected to the apocalypse, and that she was being commanded to mutilate herself and her child.

In the hours following her detention, authorities reported observing her murmuring prayers, repeatedly thanking Jesus.

She was initially charged with murder, before medical experts concluded Schlosser was suffering from a profound psychotic break and was incapable of understanding the reality or consequences of her actions. She was determined not guilty by reason of insanity and placed in a state psychiatric facility.

Her remaining children were taken from the household, and she was permanently prohibited from having any contact with them again.