Updated

A Texas man marked 12-12-12 by carving a pentagram into the back of his 6-year-old son, telling police that he did it because "it's a holy day," authorities said.

Police tell MyFoxAustin.com that Richmond Hills resident Brent Troy Bartel called 911 just after midnight Wednesday and told a dispatcher he "shed some innocent blood." When asked to clarify, he reportedly said, "I inscribed a pentagram on my son."

Bartel, 39, faces charges of aggravated assault with a deadly weapon. He's jailed in lieu of $500,000 bond.

Officers in the Fort Worth suburb say they arrived and found that most of the child's back was covered with a large pentagram. Richland Hills police also recovered a box cutter they believe was the weapon used to cut the boy.

The child was taken to a hospital. His condition was not immediately released.

It's unclear what Bartel meant about the day or why he used a pentagram, a five-sided star that's a symbol for many pagan groups. Wednesday's date is 12-12-12, a once-in-a-century event.

The Associated Press contributed to this report.

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