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,

Speaking to reporters on Tuesday, Georgia Bureau of Investigations Director Chris Hosey said 500 shell casings were recovered from the scene, while its believed 200 rounds hit six buildings in the CDC complex. Five firearms were also recovered, he said.

All CDC employees nationwide, except for essential on-site personnel, have been instructed to work remotely on Monday as Georgia investigators continue probing Friday's deadly active shooter incident near the agency's Atlanta headquarters, according to a letter obtained by ABC News.