JACKSONVILLE, Florida - Multiple people have been killed in a mass shooting in Jacksonville, Florida, police said. The Jacksonville Sheriff's Office said authorities are responding to the Jacksonville Landing marketplace in the city's downtown area, where an esports video game tournament was being held.

The sheriff's office said one suspect was dead at the scene. They said it is unclear if there is a second suspect.

Officials are warning residents to avoid the area. "We can't stress enough to stay away. Many blocks away," the sheriff's office tweeted.

GLHF Game Bar in the Jacksonville Landing was hosting a regional esports tournament for players of EA's Madden 19 on Sunday, according to a schedule posted two days ago on the EA Sports website. Apparent gunshots can be heard in recordings from the tournament on the bar's Twitch account, which was streaming the competition.

In a Facebook message, the bar told CBS News that all staff members and the owner were able to escape "untouched."

The sheriff's office urged anyone hiding inside the building to remain calm and wait for police to reach them.

"SWAT is doing a methodical search inside The Landing," the office said. "We will get to you. Please don't come running out."

This is a developing story and will be updated.

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