Harker Heights firefighters responded to a possible gas leak around 11:30 a.m. Friday at the Sam's Club, 600 W. Central Texas Expressway.
Nobody was injured in any capacity, according to Fire Chief Paul Sims. About a dozen workers and several customers were promptly evacuated once HHFD arrived on scene.
An odor and unsafe carbon dioxide levels were reported, according to Sims. Whether a gas leak caused them is unconfirmed at this time. All gas and appliances were shut off as a precaution.
"A number of things could be causing that," Sims said.
Atmos Energy workers were also on scene sweeping through the storefront.
Officials expect to open Sam's Club once they have the "all clear." Crews were still searching the building near 3 p.m. Friday.
Lt. Stephen Miller, with Harker Heights Police Department, said a gas leak was reported in the back of the store.
This story will be updated.