TAMPA, Fla. (AP) - Three Tampa-area schools are under a modified lockdown because officials discovered a bullet on the floor of a school bus.
    
The bullet was found Monday morning. The bus had dropped students off at three schools: Liberty Middle School, Turner Elementary and Wharton High. Officials say officers from the Hillsborough County Sheriff's Office and Tampa Police are interviewing all of the students who rode that bus and searching bags and backpacks. No weapons or additional ammunition have been found.
    
School officials say the three schools are in "modified lockdown." That means that recess and other outdoor activities are allowed.
    
Because of the school shooting in Connecticut last week, Hillsborough County stepped up security and sent uniformed deputies to elementary schools on Monday.

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