The fight was reported at about 4 p.m. Saturday at the Dunkin' Donuts on Main Street, police said.
Three juveniles entered the doughnut shop and jumped an employee, Jeffrey Sumpter, 21, and began punching him, police told The Hour.
Related story: 1 Victim Seriously Injured In Stabbing Near Dunkin' Donuts In Norwalk
Sumpter had a knife and stabbed one of his attackers in the leg before they fled to the nearby Rainbow Plaza, The Hour said.
The juvenile with the serious leg wound was transported to Norwalk Hospital, The Hour said.
Sumpter was charged with first-degree assault and risk of injury to a minor, The Hour said.
Click here for the story at The Hour.
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