Hundreds of workers were evacuated from the Goodyear plant after reports of a man with a gun.
The sheriff's department says an employee reported seeing a man inside the plant with gun.
Around 450 employees were evacuated to outside the plant. Most of the workers huddled around the plant entrance, or stood around waiting, while deputies and K9s did a safety sweep inside the plant.
ABC11 has learned that someone reported a man inside the plant was wearing a handgun in a holster.
A sheriff's department spokesperson says they did not find a person with holster or handgun.
However, a sheriff's department spokesperson says workers were evacuated mainly out of an abundance of caution.
Employees were eventually allowed to go back in and resume work at the largest radial tire manufacturer in the U.S. The plant produces 30,000 tires a day.