A former Chattanooga Fire Department lieutenant was fired following a six-month investigation into allegations he had posted threats to a city councilwoman and the mayor.

According to Councilwoman Demetrus Coonrod, the social media post that resulted in the investigation and termination of 19-year firefighter Charlie Thomason included the image of bullets labeled with her name and the name of Chattanooga Mayor Andy Berke.

After the investigation into the December Facebook post, Coonrod is calling for charges against Thomason.

"Firing is not enough," she said. "It was blatantly threatening and he should be charged."

Coonrod noted that she, a black woman, and Berke, who is Jewish, were threatened by the white fireman.

"It's a perfect example of institutionalized racism," she said.

(READ MORE: Fire lieutenant resigns as Chattanooga Fire and Police Pension Fund president amid internal affairs investigation)

Fire department spokeswoman Lindsey Rogers said that Chief Phil Hyman spoke with both Coonrod and Berke after the incident.

"Both Councilwoman Coonrod and Mayor Berke were contacted right after the post was made. Chief Hyman spoke directly to Councilwoman Coonrod at city council regarding the incident," she wrote Friday. "The chief told the councilwoman that [the fire department] would follow through with the disciplinary process. He said he was extremely displeased with Thomason's behavior, as this goes against policy, and added that this is an example of conduct unbecoming of a public employee, on or off duty."

Thomason, who made more than $53,000 per year as of June 1, was put on paid leave for six months after the post while the department investigated the incident before his eventual termination from the department and subsequent resignation from the Chattanooga Fire and Police Pension Fund, where he served as president before the incident.

Rogers said the fire department brought the case to the Hamilton County District Attorney's Office, where it was decided not to press charges against Thomason.

Berke's office did not comment on the incident but directed the Times Free Press to the fire department.

Rogers said Hyman and Berke had several conversations about the incident.

Contact Sarah Grace Taylor at 423-757-6416 or at Follow her on Twitter at @_sarahgtaylor.