Authorities expected to allow everyone back in just after 1 p.m., two hours after the call, Bill Maer of the Passaic County Sheriff's Office told Daily Voice.
"The courthouse was evacuated, the K-9 and bomb squad units were going room by room, Sheriff [Richard H.] Berdnick was on-scene," Maer said around noon.
Maer said he wasn't certain what prompted media reports of a fire.
"All I know," he said, "is there were no flames, no fire."
However, a Passaic County law enforcement official with direct knowledge of the incident said the initial bulletin broadcast through the courthouse referred to a fire "in order to get people out quickly."
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