The Fulton County Courthouse in Downtown Atlanta was briefly on lockdown March21 after a suspicious white substance was found inside an envelope addressed to District Attorney Fani Willis’ office.

According to WSB-TV, an employee opened the envelope around 2 p.m. and alerted authorities after finding a white substance inside.

The Atlanta Fire Department treated four people who complained of headaches but determined the substance was non-poisonous.

The lockdown was lifted after 3 p.m. and normal functions resumed at the courthouse on Pryor Street.

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Collin Kelley is the executive editor of Atlanta Intown, Georgia Voice, and the Rough Draft® newsletter. He has been a journalist for nearly four decades and is also an award-winning poet and novelist.