ATLANTA — Emergency crews rushed to the Richard B. Russell Federal Building in downtown Atlanta Friday morning after several suspicious envelopes were discovered.

Authorities say at least three envelopes were found inside the courthouse, prompting a police and fire response. Six people sheltered in place after possible exposure, though no injuries have been reported.

Hazmat teams isolated the envelopes, and officials later confirmed they did not contain any hazardous material. It remains unclear what the envelopes held or whether they were addressed to specific individuals.

Several surrounding streets were temporarily closed during the investigation.