The incident took place in Stamford on Tuesday, April 26 at Cloonan Middle School.
In a letter to parents, Principal David Tate wrote that as a result of the fight, police were notified and responded to the campus.
"During this time, we followed our standard protocols, and the school was placed on lockdown while we resolved this isolated incident," Tate said.
The responsible students have been immediately disciplined and will face further disciplinary action under the Board of Education policies, he added.
"We make every effort to create and maintain a safe environment for all students and staff and have zero tolerance for this behavior," Tate wrote.
Because of the lockdown, scheduled assessment testing was canceled for the day and will resume on Thursday, April 28, he added.
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