VIENNA, Ill. (AP) — Authorities say a southern Illinois man allegedly shot his half-brother to death following an argument over the COVID-19 vaccine.

Sixty-eight-year-old Larry D. Cavitt of Goreville, was charged Monday in Johnson County Court with murder and aggravated battery with use of a firearm.

The charges stem from Saturday’s death of Cavitt’s 51-year-old half-brother, Joseph E. Geyman. Johnson County Sheriff Pete Sopczak says the two men, who lived next door to each other, argued over the COVID-19 vaccine before Cavitt allegedly took out a handgun and shot Geyman in the head. The sheriff tells The Southern Illinoisan that “It just makes no sense.”