A shooting at the Atlanta headquarters of the Centers for Disease Control and Prevention killed a police officer and rattled the community of public health workers, who said the attack was a manifestation of rampant misinformation surrounding vaccines.

A 30-year-old man who believed the Covid-19 vaccine had made him ill opened fire at C.D.C. buildings on Friday, according to the police. A young DeKalb County police officer was killed in the attack, and the gunman also died. On Saturday, investigators from local, state and federal law enforcement agencies were working to piece together the details and the circumstances that precipitated the attack.

The shooting came after years of conspiracy theories about vaccines and escalating political hostility toward the C.D.C., which some federal officials have sought to blame for lockdowns and vaccine mandates during the coronavirus pandemic.

Here’s what we know about the shooting.

What happened in the attack?

Shortly before 5 p.m. on Friday, the police in Atlanta received a 911 call about an active shooter at a CVS drugstore across the street from the C.D.C. headquarters on Clifton Road, near the Emory University campus and Emory University Hospital.

Dozens of bullets struck the exterior of at least four C.D.C. buildings, damaging windows and pitting the structures’ sleek glass facade. No C.D.C. employees or civilians were injured.