Bullets pierced "blast-resistant" windows, and it could take weeks or even months to repair the damage, agency officials said.

Employees at the CDC said bullets struck the windows of several buildings on the federal agency's campus.

Employees at the CDC said bullets struck the windows of several buildings on the federal agency's campus.

Bullets pierced "blast-resistant" windows, and it could take weeks or even months to repair the damage, agency officials said.

Police say more than 500 shots were fired at the Georgia campus, where a police officer was killed.