A high school student confessed to a deadly attack at a Texas track meet, prompting grief and renewed attention to safety protocols at school sporting events.

Karmelo Anthony, 17, admitted to police he fatally stabbed another student during a high school track meet in Frisco, telling an officer, “I’m not alleged, I did it,” according to an arrest affidavit obtained by NBC 5 DFW.

Anthony, a student at Centennial High School, is charged with murder in the death of 17-year-old Austin Metcalf of Memorial High School. The incident occurred on April 3 at Kuykendall Stadium following an altercation during a rain delay.

A witness reportedly said Anthony unzipped his bag, warned Metcalf, “Touch me and see what happens,” then stabbed him once in the chest after Metcalf allegedly grabbed him.

Metcalf died in the arms of his twin brother, according to their father. Anthony claimed self-defense and asked officers whether the stabbing would be considered justified. He remains in the Collin County Jail on a $1 million bond. If convicted, he faces up to 99 years in prison.

Frisco Independent School District (ISD) and police declined further comment. School security expert Craig Miller noted metal detectors are not typically used at such events. Memorial High paused Thursday to honor Metcalf, as the community rallies around his grieving family.