Katherine Koonce was one of six people shot dead at Covenant School on Monday as Audrey Hale went on a bloody rampage with two assault rifles and a 9MM semi-automatic.

The head of school had previously prepared her students and staff for an active shooter situation and fearlessly sprang into action when the bullets started flying.

Nashville City Councilman Russ Pulley told FOX News that Koonce, 60, promptly ended a Zoom meeting after the first gunshot and didn't think twice about going after the 28-year-old Hale.

Pulley said, "She immediately ended the call, got up and headed straight for the shooter," indicating that Koonce may have clashed with Hale in a hallway.

Pulley added, "She did what principals and headmasters do; she protected her children."

Nashville Police Chief John Drake confirmed at a Tuesday press conference that Koonce was involved in a "confrontation, I’m sure – you can tell the way she was lying in the hallway," but Drake did not elaborate.

Koontz's local pastor, John Bourgeois, celebrated her selfless act in a message to his congregation at West End Community Church in Nashville. Bourgeois wrote, "She gave her life in defense of the children under her care."

Police say two of Koontz's colleagues, both 61, were also murdered: Cynthia Peak, a substitute teacher and Mike Hill, a custodian. In addition, three 9-year-old students were killed: Evelyn Dieckhaus, Hallie Scruggs and William Kinney.

Two cops were seen on body cam footage fatally shooting Hale on the second floor of the private Christian elementary school.

Chief Drake said Hale had written a manifesto detailing the deadly attack and listing other potential targets. The contents of the manifesto were not disclosed.

Drake also said Hale -- who was a biological female but identified as male -- was a former student at the school and resented having to attend classes there, which was "why this incident occurred."