(JACKSONVILLE, Fla.) -- Multiple fatalities were reported in a mass shooting that erupted Sunday afternoon at a Madden NFL e-games tournament in a popular area of Jacksonville, Florida, sheriff's officials said.
It was not immediately clear how many victims were killed or injured in the incident, which occurred just before 2 p.m. in the Jacksonville Landing section of the city.
"Multiple fatalities at the scene, many transported," the Jacksonville Sheriff's Office tweeted at 2:45 p.m.
The suspect was dead at the scene, officials said.
Jacksonville Sheriff Mike Williams said at a press conference that there were no outstanding suspects, that the Jacksonville Landing had been searched and cleared and that witnesses were being interviewed.
"One suspect is deceased ... we are still working to confirm his identity," Williams said.
At least nine people, ranging in age from 20 to 35, were injured in the shooting and treated at two local hospitals, University of Florida Health Hospital and Memorial Hospital, officials said. Six of the victims were listed in good condition, one was in serious condition, and three were treated and released, officials said.
Williams did not say how many people were killed.
The shooting broke out at a sanctioned Madden NFL 19 Classic qualifier event at the GLHF Game Bar in the Jacksonville Landing area. Madden NFL is a video football game named after former Oakland Raiders' head coach and NFL analyst John Madden.
"I was working ... and the next thing you know, I hear gunshots," Brianna, an employee at the Chicago Pizza in the Jacksonville Landing, told ABC affiliate station WJXX-TV in Jacksonville. "I look over and see people running, just going crazy."
She said a gamer participating in the e-game tournament told her that the gunman was arguing with another gamer, then went to the back of the venue, where he waited a few minutes before hoping fire.
Brianna, who did not give her last name, said a security guard told her to go hide.
"As I was hiding, I called my mother to let her know I was OK," Brianna said.
Williams said the shooting happened in one of the restaurants in The Landing, but he would not say which one.
He said investigators have obtained a video of the shooting and asked anyone with more video to contact the sheriff's office.
In a video of the shooting circulating on social media, at least 11 gunshots could be heard, followed by people screaming.
Witnesses told WJXX-TV that the shooting occurred after an argument flared up over the Madden e-game competition. ABC News has not been able to independently confirm the witnesses' statements.
"We are finding many people hiding in locked areas at The Landing. We ask you to stay calm, stay where you are hiding," the sheriff's office said in a tweet. "SWAT is doing a methodical search inside The Landing. We will get to you. Please don't come running out."
Electronic Arts, publisher of the Madden NFL e-game, confirmed that the shooting broke out during the tournament, which drew players from across the nation.
"We are aware of the incident at a sanctioned Madden Championship Series competition in Jacksonville. We are working to gather facts at this stage," the company said.
Earlier the sheriff's office tweeted, "#LandingMassShooting at the Jacksonville Landing. Stay far away from the area. The area is not safe at this time," the Jacksonville Sheriff's Office tweeted Sunday afternoon.
ATF and FBI Agents were headed to the scene to assist in the investigation, the agencies confirmed.
President Donald Trump has been briefed on the shooting, said White House press secretary Sarah Sanders.
Florida Gov. Rick Scott said in a tweet that he was briefed on the incident by Jacksonville Sheriff Mike Williams and that the state was ready to offer any resources needed in the investigation. He said the Florida Department of Law Enforcement was also sending resources to the scene.
Scott spoke by phone with President Trump, who offered federal resources to help in the investigation. The governor was traveling to Jacksonville from Naples, Florida, Sunday evening.
The Jacksonville Sheriff's Office is asking anyone with information about the shooting to contact them immediately by calling their hotline at (904) 630-0500 or their tip line at (866)845-TIPS.
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