A gunman who shot 12 people, killing two, at a Florida video game tournament "clearly targeted" other gamers, officials said Monday.

The gunman, David Katz, 24, also killed himself inside a gaming bar at Jacksonville Landing, a collection of restaurants and shops in the city.

Jacksonville County Sheriff Mike Williams told reporters that Katz, of Baltimore, had relationships with the victims, although it wasn’t clear with whom.

"This group travels as a circuit," he said, referring to players of the Madden 19 football video game by EA Sports.

The weekend’s event was the game's Southeastern Qualifier Tournament with a $5,000 prize pool. Katz is listed online as a 2017 championship winner.

Williams said that Katz had ammunition and two handguns with him during the shooting, a .45-caliber and a .9 mm, though authorities believe he only fired one. The firearms were bought legally in Maryland, Williams said, adding that one of them was equipped with an aftermarket laser site.

One of the victims, Elijah Clayton, was a 22-year-old video game champion from Woodland Hills, California, who was known as "Trueboy."

In a statement Monday, a cousin, Brandi Pettijohn, described Clayton as a peaceful man who excelled at Madden and used his earnings to fund his education.

"He never even had a fist fight," Pettijohn said, adding: "He loved football, and out of all the video games he could play he settled and mastered Madden. He made a good living gaming and he saved his earnings so he can afford to go to college."

Taylor Robertson, 28, of Giles, West Virginia, also died in the shooting. Robertson went by the handle "SpotMePlzz."

In a statement late Monday, Electronic Arts CEO Andrew Wilson described Clayton and Robertson as "two of our top Madden competitors."

"They were respected, positive and skilled competitors, the epitome of the players and personalities at the heart of our community," he said.

Wilson said the company canceled three remaining qualifying events in the competition while it reviewed security protocols and worked with "our partners and our internal teams to establish a consistent level of security" at gaming events.

"This is the first time we’ve had to confront something like this as an organization, and I believe the first time our gaming community has dealt with a tragedy of this nature," Wilson said.

Everyone shot in the incident — as well as one person who suffered an unspecified wound — was expected to recover, Williams said. There were roughly 150 people at the bar for the event, he said.

"As bad as this is it could have been much worse," Williams said.

Williams declined to discuss a possible motive, saying authorities were still investigating Katz’s background and searching his car and hotel room.

No notes were left and he did not appear to have said anything during the shooting, Williams said.

Charles Spencer, special agent in charge with the Federal Bureau of Investigation, said Katz’s mother and father in Baltimore were cooperating with authorities.

"This has been vital to advancing the overall investigation," he said.

Court records obtained by The Associated Press showed that Katz was twice hospitalized in psychiatric facilities more than a decade ago, when he was a young teenager. The records, which were included in a 2007 divorce filing, say that he was prescribed anti-psychotic and anti-depressant medications, the AP reported.

The records show that Katz’s father believed his mother was exaggerating their son’s symptoms of mental illness during a custody battle, the AP reported.

The shooting occurred on Sunday around 1:30 p.m., a couple of hours after the tournament’s group play began. Firefighters who had just completed a training across the street recalled seeing a mass of people flood out of The Landing, including some with gunshot wounds.

"More and more people are running out saying, 'There's multiple people shot — he's shooting inside the landing,'" recalled firefighter Eddie Wallace in an interview with NBC News. "And there [are]...probably at least 100 people running out of The Landing screaming, 'call 911.'"

An announcer at the event, Toshiba Sharon, 39, said he dropped to the ground and flipped over a table when he saw the gun’s laser site.

After seeing the shooter pointing into the room, multiple friends were struck by gunfire — including a fellow commentator sitting beside him, he said.

It was an "ugly scene," Sharon said, adding, "To those families, I just wanted to let them know that their loved ones didn't die alone. They died amongst their extended family and that's the brotherhood of Madden."