Officials are still investigating a shooting at the Centers for Disease Control and Prevention headquarters in Atlanta, Georgia, that killed a police officer on Aug. 8. The suspect, Patrick Joseph White, 30, may have been disgruntled over vaccine side effects before perpetrating the shooting, according to multiple reports.

Officer David Rose, 33, was shot while responding to the gunfire, the DeKalb County Police Department said in a news release. He was transported to nearby Emory University Hospital where he died of his injuries. Newsweek has contacted the police department for further comment via email.