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.

Authorities said Tuesday that investigators recovered at least 500 shell casings at the scene, estimating that White fired more than 180 shots at the CDC headquarters using his father’s long gun. White shot and killed himself at the scene before responding officers could reach him.

A Georgia man who had blamed the COVID-19 vaccine for making him depressed and suicidal has been identified as the shooter who opened fire late Friday on the U.S. Centers for Disease Control and Prevention headquarters,