Shortly before 8 p.m. Wednesday, the 911 dispatch at the Clay County Sheriff's Department received a call from Great Dane Trailers, 2664 E. U.S. 40, reporting a possible bomb threat in the "thermo-cube" area of the plant.
As a precaution, more than 300 second-shift employees were evacuated from the plant while it was searched for possible explosives.
None were located, and employees were allowed to return to work around 9:30 p.m., with the recommendation to check every area for any unauthorized packages.
Great Dane Human Resources Manager Mike Steed said, "The situation was handled appropriately and the employees were never in any danger."
The Clay County Sheriff's Department investigation is being continued.