Documents found in a search of the suspect’s home “expressed the shooter’s discontent with the COVID-19 vaccinations,” Georgia Bureau of Investigation Director Chris Hosey said.

A search of Patrick Joseph White’s home revealed documents in which he indicated his discontent with the vaccine, they said.

CDC security guards stopped White from driving into the campus on Friday before he parked near a pharmacy across the street and opened fire from a sidewalk. The bullets pierced “blast-resistant” windows across the campus, pinning employees down during the barrage. More than 500 shell casings were recovered, the GBI said.