Chief Castor takes questions about Friday's find.

TAMPA (FOX 13) -

Tampa police say they've confiscated bricks and pipes from a rooftop in Tampa, and discovered what they say is "anarchist" graffiti.

The anonymous symbol was spray painted, along with the number "99" in red paint.

All of it was found on top of a building at 1000 North Florida Ave., which is at the corner of Florida Avenue and Tyler Street.

"We are appreciative that the business owner called us," Tampa Police Chief Jane Castor said Tuesday afternoon. 

"Finding those items for us was not a surprise," she added.  "We are just pleased to see the communications process worked the way it did."

Bill Warner is a private investigator who tracks and researches radical groups all over the world. He says the stockpile is a sign of trouble ahead.

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