This post was updated at 4:45 a.m. September 17, 2019. 

OCEANSIDE, N.Y. (CBSNewYork) — One teenager is dead another is injured after a large brawl outside a Long Island pizzeria Monday afternoon.

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(Photo: CBS2)

It happened around 3:45 p.m. at a strip mall on Brower Avenue in Oceanside, CBS2’s Ali Bauman reports. The strip mall is located about a block from Oceanside High School.

Nassau County Police say dozens of high school students were hanging out outside a pizzeria after school when a group of about six teenage boys drove up and a fight broke out.

Officers say 16-year-old boy Khaseem Morris was stabbed in the chest and an 18-year-old boy suffered a broken arm and swelling to the head.

“During this attack, one of the victims was stabbed multiple times in his upper body. He’s now taken to a local hospital where he’s fighting for his life right now,” Det. Lt. Stephen Fitzpatrick said.

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Police believe this was a premeditated, targeted attack.

(Credit: CBS2)

“This has been and always has been a local gathering for at least Oceanside High School to spill out and go to pizzeria and all the stores here. Now, if these kids are from another area and they came here with a vendetta, whatever their motive was, they knew where to find them,” Fitzpatrick said.

Investigators are reviewing cell phone video that has been circulating on social media, and police have been questioning some of the approximately 50 teens who were there, trying to determine the motive.

“It might’ve been over a female, it might’ve been over a school rivalry, but we’re learning towards the first part of that,” Fitzpatrick said.

“I’m in shock. Oceanside? … This is a safe area, so you send your children to the school because there’s never a problem like that,” parent Anna Vargas said.

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No weapons have been recovered. No arrests have been made, and police are still looking for several individuals who are considered persons of interest.