The suspect has been identified as a white male.
The shooting happened in the Jacksonville Landing complex as a video game tournament was being held. Several shots could be heard in a video that appeared to show the event being streamed on line.
People were playing the American football game Madden at the time.
“We believe the suspect to be 24-year-old David Katz from Baltimore and the FBI is assisting us with that leg of the investigation in Baltimore.” said Jacksonville Sheriff Mike Williams.f
People fled for shelter when the shooting began.
Police used social media to appealed to them to stay calm as Swat teams moved in.
Florida has seen several mass shootings in recent years, including at the Pulse nightclub shooting in Orlando in 2016, when 49 people died.
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