The fire district received a call at 11:44 a.m. reporting that employees at a business in the 2500 block of Bates Avenue were smelling an odor believed to be sewer gas, Hopkins said.
The fire district evacuated the building and called the county's hazardous materials team.
Hazardous Materials Program Director Randy Sawyer said work being done on the sewer system appears to have released the odors.
According to Sawyer, five or six people reported feeling ill. Hopkins said three or possibly four people were taken to a local hospital.
Hopkins said health officials were continuing to check on the rest of the people who might have been exposed to the gasses and the building was still evacuated as of 1 p.m.