CNN is reporting that a gunman opened fire at a Madden gaming event in Jacksonville, Florida, on Sunday, and multiple fatalities are reported.

The Jacksonville Sheriff’s Department posted a notification on Twitter, saying that the shooting occurred at Jacksonville Landing, a shopping mall in the city, and warned people to stay away while they secured the scene. The sheriff’s office confirmed that there were “multiple fatalities,” and that one suspect has been killed.

The event was being live-streamed, and in the video, several gunshots and screams can be heard before the video stops. Jacksonville sheriff deputy Mike Williams confirmed that his office had the video, and encouraged anyone with additional footage to turn it over to authorities. He also says that his office is working with witnesses to figure out how the incident played out.

At 4:30PM ET, Sheriff Williams provided an update, saying that they had cleared the scene, and confirmed that a white male shooter was dead and that there were no additional suspects. He also confirmed that there were multiple people who were killed on the scene, and there were additional victims transported to local hospitals.

Several hours later, authorities said that they believe the shooter is 24-year-old David Katz, of Baltimore, Maryland, who died of a self-inflicted gunshot. He was one of the three people killed at the scene; 11 other people were wounded. They also say that they’ve located Katz’s vehicle and are continuing to investigate his actions prior to the attack. The Baltimore Sun says that “federal authorities were at were at a home in the 1200 block of Harbor Island Walk near Baltimore’s Inner Harbor on Sunday night as part of an investigation into the Jacksonville mass shooting.”

The event was a qualifying match for the Madden 19 Tournament at the GLHF Game Bar, according to one of the teams that was participating. According to EA, it was one of four qualifiers that would advance teams to a Las Vegas event in October.

Drini Gjoka, a member of the compLexity team, reported that he had been shot in the thumb, and another player reported that he was hit twice. Steven Javaruski reported that police escorted him out of the building.

On Twitter, EA said that it was “aware of an incident at a sanctioned Madden Championship Series competition in Jacksonville. We are working with authorities to gather facts at this stage.”

Update August 26th, 4:40PM ET: This story has been updated to reflect information from the Jacksonville Sheriff’s Office.

Update August 26th, 9:16PM ET: This story has been updated to reflect additional information from the Jacksonville Sheriff’s Office, including the identity of the suspect.