Documents found in a search of the home where Patrick Joseph White lived with his parents “expressed the shooter’s discontent with the COVID-19 vaccinations,” authorities 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.

Grappling with the aftermath of a shooting that killed a police officer and left nearly 100 shattered windows, leaders at the Centers for Disease Control and Prevention held virtual meetings with employees on Tuesday to rebuild trust at the agency's Atlanta headquarters.