"More shots fired, additional shots fired" were the words heard on the police scanners shortly before 8 a.m.
As authorities were dispatched to the scene, the calls intensified. "We're coming up to the front door," officials said. "We've got shots fired right now, guys."
According to law enforcement agencies, the suspected shooter appears to be a student.
Listen to the terrifying moments recorded in the call above as the shooting unfolded.
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