Multiple people were said to be dead Sunday afternoon after a mass shooting at bar in Jacksonville, Fla., that was hosting a live gaming event, police said.

According to The New York Times and other news organizations, at least 12 gunshots were heard at the event. Preliminary reports suggested at least 11 people were shot, CNN reports. Four were killed, the report says.

The gunman was dead at the scene but it was unclear if there was more than one assailant, the Times reported. Officials said searches are ongoing. The incident took place at the GLHF Game Bar, the Times reported. The public was able to follow the tournament on a gaming network called Twitch, according to the Times.

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Users of Twitter were following the harrowing developments unfold live, as law enforcement used the social media site to get out crucial information.

The Jacksonville Sheriff’s Office echoed the severity of the incident, tweeting Sunday afternoon: “Mass shooting at the Jacksonville Landing. Stay far away from the area. The area is not safe at this time. STAY AWAY #TheLandingMassShooting.”

The agency later tweeted that officers were finding may people hiding in locked areas at The Landing. “We ask you to stay calm, stay where you are hiding,” the agency tweeted a little before 3 p.m. ET. “We will get to you. Please don’t come running out.”

The agency also used Twitter to ask people who were hiding to call 9-1-1.

Just before the shots were heard, a red laser appeared on the chest of one of the players in the live gaming event, and the video of the players then vanished, the Times reported.

Sujeil Lopez of Tampa Bay, Fla., told the news organization that she’d just received a call that her son, Larry, 25, had been shot.

“I have to get to him,” Lopez told the Times. “I am four hours away from him and I have to get to my son.”

She added that her son was shot three times and she did not know his condition.

Lopez’s son is a professional video game player for the Bucks Gaming team, the Times reported, basing the information on Lopez’s Twitter profile.

Another Twitter user, Drini Gjoka, said he’d been shot in the thumb.

“The tourney just got shot up,” Gjoka posted. “I will never take anything for granted ever again. Life can be cut short in a second.”

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