The Westfield Southgate Mall in Sarasota, Florida is closed on Tuesday afternoon as police investigate an unknown substance which is being described as a white powder.
Just before noon, someone walked into the Lens Crafters store and threw an unknown substance and fled the area, reported ABC.
The Sarasota County Fire and Sarasota Police have responded.
The mall is closed as the investigation takes place.
People inside are being asked to shelter-in-place.