A grandmother employed a sledgehammer and carving knife to brutally murder her infant grandchild, prosecutors said in a Chicago court on Monday.

Assistant State Attorney Michael Deno said 61-year-old Alfreda Giedrojc committed the heinous act against 5-month-old Vivian Summers Sunday morning after she had been dropped off by her father, according to the Chicago Tribune.

No Headline Can Capture the Inexplicable Horror of Exactly How a Chicago Woman Killed Her Infant Granddaughter

Alfreda Giedrojc, 62, was charged with first-degree murder for allegedly murdering her granddaughter with a sledgehammer and carving knife. (Image source: Oak Lawn Police Department)

Giedrojc has been charged with first-degree murder and is being held without bond at the Cook County Jail.

The infant was resting on the couch when Giedrojc allegedly went to the closet and pulled out a sledgehammer.

“The defendant then hit the victim repeatedly in the head and body with the sledgehammer,” Deno said, according to the Tribune. “Since the victim was still crying and moving, the defendant then went to the kitchen and retrieved a large carving knife.”

“The defendant then picked the victim up, held her and then slit her throat with the knife,” he added.

Deno told the judge that Giedrojc admitted to murder in a videotaped statement and that authorities did not speculate about what her motive was, according to the South Town Star.

Authorities also declined to answer questions about whether she had a history of mental illness.

Oak Lawn Police Chief Michael Murray said his department responded to a call at 10:46 a.m. and was stunned by what they discovered.

“I have never seen anything like this. It’s a tragedy,” he said, according to the South Town Star. “Our thoughts and prayers go out to the family. This is going to be a very difficult time for everyone, including our officers and the people who responded to the scene.”

Neighbors, as well, were shocked to learn of the scene that had unfolded next door.

“Never in my life would I ever have believed this could happen,” neighbor Carrie Lynn Hennessy told the Chicago Tribune. “You have to just pray for the whole family.”

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