Background: The 1200 block of Bliss Drive in Bellefontaine Neighbors, Missouri (Google Maps). Inset: Craig Jones (St. Louis County Police Department).

Authorities in Missouri allege that a man harbored intentions to commit murder for about a week before he attacked his sister with a dumbbell and then fatally stabbed her.

Court documents indicate that Craig Jones, aged 22, faces charges of first-degree murder and armed criminal action for the killing of Taylar Hill. This tragic event took place in a St. Louis suburb on Tuesday evening.

Jones, along with his sister, was present at a residence on the 1200 block of Bliss Drive in Bellefontaine Neighbors on Tuesday evening when he purportedly assaulted her multiple times on the head with a seven-pound dumbbell, as outlined in a criminal complaint reviewed by Law&Crime. Following the assault, he allegedly “retrieved a steak knife and stabbed the victim” multiple times.

It is reported that Jones “fled” the location. Law enforcement officers were alerted about a stabbing and arrived at the scene shortly after 8 p.m., the Bellefontaine Neighbors Police Department stated. They found her with “life-threatening stab wounds,” and although she was rushed to a nearby hospital, she succumbed to her injuries.

Local CBS affiliate KMOV reported that Hill was 26 years old.

Upon request from the Bellefontaine Neighbors Police Department, the St. Louis County Police Department took over the probe. The complaint notes that police later located Jones and “took him into custody without incident.”

He then reportedly shared a shocking admission of guilt.

Jones “confessed to police that he murdered his sister and had been planning on killing someone for approximately a week,” according to the court document.

He “intentionally killed his unarmed sister without provocation,” the complaint added.

Jones was scheduled to be arraigned on Thursday.