Two people remain hospitalized in connection to that accident. There is no word on their condition.
An investigation into previous safety violations at the plant show this is not the first time an on-the-job injury has landed workers in the hospital.
In June of 2012, five employees at Smithfield's Tar Heel plant were hospitalized after someone mistakenly activated an evaporator, releasing 69 pounds of ammonia on an overhead catwalk inside the plant.
Smithfield was ordered to pay the state a $97,000 fine to settle that case, after investigators found 29 safety violations.
That was by far the most serious incident in recent years at the Tar Heel plant, but we found nine different inspection reports that uncovered over a dozen other violations resulting in $60,000 in other fines.
We also found that at the Smithfield plant in Clinton, a worker died by asphyxiation in 2012 while filling a tanker with waste water sludge and being overcome by hazardous fumes. The company was fined $162,000 following that incident.
State regulators said animal slaughtering and processing is a high hazard industry, and a certain number of injuries each year are typical.
The Smithfield plant in Tar Heel is the largest pork processing plant in the world, with about 2,400 employees. The plant was evacuated after Tuesday's ammonia leak, and will resume operations Friday morning.
Copyright 2014 WECT. All rights reserved.