Gunman Patrick Joseph White expressed discontent with the COVID-19 vaccinations in writings he made before the shooting, authorities said.

Patrick Joseph White, a 30-year-old from Cobb County, opened fire on the CDC headquarters on Friday. White shot DeKalb police Officer David Rose, who later died at the hospital. White died from a self-inflicted gunshot wound.

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.