David Katz, who is believed to be the suspect in the Jacksonville, Florida, video game tournament shooting, was 24 years old and from Baltimore.

He had come to Florida to participate in the Madden NFL 19 competition at the Jacksonville Landing entertainment complex, which was live streamed on Twitch, where the shooting can be heard. The competition was held in a gaming bar that shares space with a pizzeria. Viewers can watch the games online and see the players.

Jacksonville Sheriff Mike Williams said authorities believe Katz carried out the attack using at least one handgun. Williams said the suspect died from a self-inflicted gunshot, adding authorities were still making final confirmation of his identity with the FBI assisting them in Baltimore. Two other people died and nine were injured.

More from USA Today:

Katz allegedly got upset about losing the game, according to some media reports.

The game's maker, EA Sports, lists a David Katz as a 2017 championship winner.

Katz was active in eSports, tournaments where video game players compete, and get seen on social media playing. He was believed to be known as "Bread" and won the February 2017 Buffalo Bills tournament of the Madden NFL football game.

Contributing: The Associated Press