BALTIMORE – Heavily armed agents late Sunday have entered the upscale Baltimore townhouse that belongs to the father of the gunman who opened fire during a Madden 19 NFL tournament at a restaurant in Jacksonville, Fla., killing two and injuring 11 before killing himself.

David Katz, 24, of Baltimore, was believed to have fired shots during the event at the Chicago Pizza restaurant and bar in The Jacksonville Landing, Sheriff Mike Williams said at a news conference. Williams did not speak about a possible motive.

The finalists in Sunday’s regional video game tournament would proceed to the Madden Classic in Las Vegas, where the top prize is $25,000. Katz, a slender 24-year-old who nicknamed himself “Bread,” had traveled from Baltimore to compete — only to be eliminated, witnesses said.

An FBI spokesman, Dave Fitz, confirmed agents had gone to the upscale townhouse home. But he did not immediately release any other specifics, citing an ongoing investigation.

The agents could be seen inside the home Sunday evening near Baltimore’s Inner Harbor. They wore raid gear and carried long guns. Reporters who gathered outside did not see any authorities carrying any bags of evidence outside.

Katz has been described by witnesses and people who knew him as a gamer who erupted in anger after losing the event, reported Fox News.

Katz died from a self-inflicted gunshot wound after he shot multiple people, police said. In addition to the dead, 11 other people were injured — nine of them with gunshot wounds.

Katz, whose vehicle was located and impounded by investigators, is believed to have stayed somewhere locally on Saturday night before the shooting.

Jacksonville killer

David Katz, 24, of Baltimore, was believed to have fired shots during the event at the Chicago Pizza restaurant and bar in The Jacksonville Landing, Sheriff Mike Williams said. (Screenshot Fox News broadcast)

The Jacksonville Sheriff’s Office added that there’s “cooperation” in Baltimore with the ATF and FBI as part of the investigation.

An eyewitness to Sunday afternoon’s mass shooting told Fox News that the gamer, now identified as Katz, had been eliminated from the tournament before he opened fire.

The witness, who declined to be identified by name but said he was 30 years old, said he did not know the shooter’s identity but noted there were “multiple guys who were upset” at being eliminated from the event.

“I know the person was a gamer, for sure. I know that they did lose, for sure,” he said. “I don’t know if they came back, I don’t know if they went to get a gun, I don’t know if they had it on them. I really can’t tell you that.”

The witness told “America’s News HQ” that he had just stepped outside the bar where the event was taking place when the gunshots rang out.

“I saw the door bust open and three or four girls kind of, like, fall over themselves to get out of the establishment. At that point, I didn’t know what was going on, but I could tell from the look on their face that they weren’t joking around or anything like that.”

The witness added that he then heard one of his friends repeatedly shout, “I’m hit! Get help!”

“I didn’t know where he was … but when people started to run, I just literally started to do the same,” said the man, who added that some friends had died in the shooting.

The witness added that a friend who was inside the bar when the shooting started told him that “a lot of the guys actually barricaded themselves in a very large bathroom … there was really no way to escape from where we were playing. You were pinned in there.”

One gamer competing at the tournament, Stephen Javaruski, told the Los Angeles Times the gunman “targeted a few people” before he killed himself.

At the end of it, Katz and two of his competitors were dead: Elijah Clayton and Taylor Robertson — better known to their rivals and fans in the gaming world by the handles they adopted for the screen.

“RIP to Trueboy and Spotme,” Javaruski tweeted. “This is the worst day of my life.”

Gaming tournaments are common in the increasingly lucrative world of professional gaming. Talented gamers and personalities who take up popular titles such as “Madden” and “Overwatch” can harness social media to rack up fans and endorsement deals while earning advertising revenue from streaming video services. The online audiences can be massive.

And just like in the living room — where emotions can run so high that players use the term “rage quitting” for sore losers who won’t play to the end — professional matches can be tense. The stakes can be thousands of dollars, larger audiences and sometimes just honor.

But the violence is supposed to stay onscreen.

The start of the shooting was captured on the livestreaming network Twitch, which broadcast footage of the restaurant and the game. A red laser dot can be seen on Clayton’s sweater before the stream’s video feed switched to a kickoff return.

Then 11 gunshots can be heard as the video feed was quickly replaced by the message “controller disconnected.”

The wounded included gamer Tony “GTech” Montagnino of Austin, Texas, whose daughter was due to start school Monday, according to the Times report. Drini “Young Drini” Gjoka, a player from Washington, D.C., was shot in the hand. “InfamousGuru” was shot in the arm. George “Fitzmagic13” Amadeo, a 17-year-old from Belford, N.J., was shot and wounded so seriously that fellow players started a GoFundMe campaign so that his family could travel to see him at the hospital.

This weekend’s tournament was sanctioned by EA Sports, which owns the Madden franchise.

“We are working with authorities to gather facts at this stage,” EA Sports tweeted. “This is a horrible situation, and our deepest sympathies go out to all involved.”