The incident left one person dead and at least six others injured. The victim who died has been identified as Malek Shepherd, 23, of New York City.
It happened around 9 p.m. Saturday at the Chick-fil-A on Route 22 in Union.
While no arrests have been made, the shooting is believed to be a targeted incident stemming from a drug or gang dispute.
Video appears to show people running away from the restaurant, but it is not yet clear how many gunmen were involved.
Shepherd, who was a customer, is believed to be the target of the shooting and the other victims are believed to be bystanders and/or employees of the Chick-fil-A.
One of the injured victims is a high school student who was working there that night trying to earn money for prom and college.
Her mother says one of her happy places has turned into a lifelong fight against trauma and she is now cringing at the thought of even stepping outside.
Eyewitness News spoke to a father of one of the Chick-fil-A workers on Saturday night. He says that his son called him in a panic, saying that multiple suspects wearing masks entered the establishment. He also says several of his son's co-workers were injured in the shooting.
Witnesses say they heard at least seven shots piercing into the crowd.
Jean Derilus, a DoorDash driver, said Monday that the masked suspects were behind the counter and firing shots into the dining area.
Derilus said Saturday nights draw a lot of other delivery workers due to the high volume of orders. He said he was in the restaurant 15-20 minutes before the shooting happened.
Longtime customers said they are shaken by the violence.
"That's what's terrifying, being a father or a parent, you have to always be vigilant and keep your head on a swivel and make sure that you're paying attention to your surroundings and try to avoid getting yourself into a situation and unfortunately coming to a Chick-fil-A at dinner time is apparently a situation you may have to avoid now a days," customer Christopher Devido said.
The other victims were treated for non-life threatening injuries.
The Union County Prosecutor's Office says it is an ongoing investigation.
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