Updated at 5:00 p.m. ET Sunday
A "mass shooting" has taken place at a shopping center in downtown Jacksonville, Fla., according to the sheriff's office, resulting in "multiple fatalities."
It happened at a Madden video game tournament, according to multiple reports.
"Multiple fatalities at the scene, many transported," the sheriff's office said on Twitter.
A white male suspect is dead at the scene and authorities are working to confirm his identity, Sheriff Mike Williams said at a press briefing. He added that officials "have no outstanding suspects at this time."
The incident happened at The Jacksonville Landing, a waterfront shopping mall and live entertainment space in downtown. Williams said they had finished securing the scene.
"The tourney just got shot up," said a player named Drini Gjoka. "I am literally so lucky. The bullet hit my thumb. ... Worst day of my life."
"They took me to the hospital. Bullet grazed my head. I feel fine, just a scratch on my head. Traumatized and devastated," said another player known as Dubby.
"Stay far away from the area. The area is not safe at this time," the sheriff said in a tweet as the incident was unfolding. "STAY AWAY."
The GLHF Game Bar at the Landing posted on Facebook that "All GLHF staff are safe and accounted for." The venue was hosting the EA Madden Southeastern Qualifiers Playoffs on Sunday, according to its Facebook page.
The official Twitter account for EA SPORTS Madden NFL said it was aware of the incident and "working with authorities to gather facts at this stage." It added: "This is a horrible situation, and our deepest sympathies go out to all involved."
SWAT teams conducted searches of the area and asked people at the scene to remain hidden in place and call 911.
The sheriff said investigators have a video that has circulated on social media, showing players competing on a big screen when suddenly the sound of gunfire and screaming can be heard. He said authorities planned to release more information later on Sunday.
Florida Gov. Rick Scott said he's spoken to the sheriff's office "to offer any state resources it may need." White House Press Secretary Sarah Sanders said President Trump has been briefed on the situation in Jacksonville.
This is a developing story. Some things that get reported by the media will later turn out to be wrong. We will focus on reports from police officials and other authorities, credible news outlets and reporters who are at the scene. We will update as the situation develops.