MARSHALL COUNTY, KY (KFVS) - When the shots rang out on Tuesday morning, students ran for safety while the first responders headed toward the danger.
We got an inside look at the response through some of the scanner traffic from the Marshall County Sheriff's Department and Kentucky State Police.
A simple request came from inside Marshall County High School.
"Central, I need some help out here at the high school."
Within seconds, the terrifying reason was revealed.
"We do have a shooter."
Marshall County sheriff's deputies and Kentucky State Police were sent scrambling to the school filled with roughly 1,400 people. Almost all of them were kids.
"Central. All available units....commons area of the high school."
First responders swarmed the building, but couldn't find the shooter.
"Central, I cannot find him. He's still on foot somewhere."
While some continued to hunt.
"He ran out the back of the commons..."
Others made horrifying discoveries.
"We got three down in the commons. One shot in the head, one to the back, one to the abdomen. One is unresponsive in the commons."
Police can't be sure how many shooters there are, but, "As far as they know, it's one shooter. He's still on the scene."
And then someone sees him.
"One to all units. We've got him spotted in the weight room possibly."
The rampage ended when a Marshall County sheriff's deputy confronted the 15-year-old suspect.
"Sixty Mayfield...want to confirm that with Central."
Fourteen minutes after the first call for help crackled across the scanner, it was over.
"One Central. Over here at the weight room. We got one in custody."
By the end there were 20 victims.
On Wednesday night, four were still recovering at the Vanderbilt Medical Center in Nashville, Tennessee.
One of the victims was listed in critical but stable condition and the other three were upgraded to stable condition.