The shot was fired around 2:10 p.m. at the 1250 State Street school. The bullet flew down a hallway and busted out a window, but no one was injured, Springfield police said.
Officers said a student opened a security door to allow the two assailants into the school. They attacked a student and fired the gun during the fight.
One of the attackers was caught but a second was able to escape. Police are searching for him.
Officers did not release their names.
This is a developing story. Check back with the Daily Voice for updates.
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