Officer Bart Chandler helped guide officers through the school to respond to the call for help.

At the time, Dalton Middle School did not have a full-time SRO, so Officer Chandler was splitting his time between the middle and high school campuses.

When the call came in, Chandler was five miles away. Channel 3 rode along with him to talk about what happened next.

"The biggest thing was to get back on campus,” Officer Bart Chandler of the Dalton Police Department said.

Officer Chandler relayed information to dispatchers.

"I was trying to make sure they knew where exactly they needed to go once they got on campus and take them to that door,” Officer Chandler said.

That door led to classroom 413 where police said teacher Randal Davidson locked himself inside with a .38 pistol.

"Just prior to crossing the intersection we just crossed, I was notified by the school staff that he had fired a shot inside the classroom. Of course that kind of amps you up a little more because now it's an active shooter situation,” Officer Chandler said.

A 911 call led police to believe a student may be inside the classroom, but that turned out not to be the case.

On our drive with Officer Chandler, it took a little over twelve minutes to get to the high school. The day of the scare, it took him half that time.

"I was driving as cautiously and as carefully as I could because I did not want to get into an accident on my way over here. If I can't make it here, I can't help anyone, but I didn't let any grass grow under my car either. It was everything the car had when I could,” Officer Chandler said.

Several patrol cruisers were already there when Officer Chandler arrived. He grabbed his long rifle and ran inside.

By then, students had evacuated and were loading buses bound for the nearby convention center.

"When I went in, it was locked down. A total lockdown. No one is moving around. Students weren't here. It was just quiet, eerily quiet,” Officer Chandler said.

He was most familiar with the school and its staff, so he was the one to call Davidson’s classroom.

"The biggest thing going through my mind at that point was just get out the room, let's get this over with and let's safely end this however we need to do so everybody goes home. I kid around with the kids all the time, but that's ultimately my mission is everybody goes home at the end of the day,” Officer Chandler said.

The negotiation lasted 20 minutes, but Officer Chandler said it felt like much longer.

"It was a long time that day,” Officer Chandler said.

A long day that ended peacefully with no injuries. Some might said Officer Chandler is to thank, but he doesn’t see it that way.

"It's not a one man show. The day happened. The day went the way it did. I did my job what I was supposed to do. I'm glad the good Lord allowed it to end the way it did and allowed it to go the way it did,” Officer Chandler said.

Randal Davidson is still in jail and faces a long list of charges.

Dalton Middle School has since filled its SRO vacancy, so Officer Chandler is back at the high school full time.

The incident has prompted discussions about school safety.

This summer, intruder locks will be installed at the high school, which will add one more layer of school security.