The attack happened around 1:45 p.m. inside the Taco Bell located at 1058 Southern Boulevard in Longwood.
When police arrived at the scene, they found a 12-year-old boy with a stab wound to the back.
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Authorities say a male suspect fled from the location.
The victim was taken to a nearby hospital, where he's expected to survive.
No arrests have been made so far, and the investigation is ongoing.
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