Authorities said retired airman Clifton Swain, 47, of Fayetteville was killed and four other employees were taken to Cape Fear Valley Medical Center from the factory, but it's not clear how they were hurt. Two of the patients were later transfered to the UNC Chapel Hill Burn Center. Their conditions are not known at this time.
The rest of the workers were evacuated from the plant. About 30 to 40 employees were working at the time of the incident. An estimated 2,500 people are employed at the plant.
"Everybody else has been accounted for and everybody else is safe except for one fatality and three injuries," Robeson County Sheriff Kenneth Sealy said.
Robeson County Manager Ken Windley said a hazardous materials team from Cumberland County was at the factory and had contained the leak.
Officials said it appeared an ammonia pipe busted inside the plant. Workers were apparently doing maintenance on a piece of machinery when the ammonia gas escaped. Though investigators called the leak an accident, an investigation is ongoing.
"ATF, SBI, and our investigators are on the scene at this time and we're working the investigation to determine what's going on," Sealy said.
Authorities had to block off part of Highway 71 in front of the plant while crews were at the scene, but were able to reopen the road around 3:30 p.m.
None of the homes or businesses nearby the plant were evacuated.
Following the incident, Mountaire Farms released a statement to the public.
"We wish to express our sincere concern and condolences for the victims and their families of this tragedy," a Mountaire Farms officials said. "We are deeply grateful for the work of the emergency and public safety officials during this crisis. We will provide whatever resources are necessary to assist local and State authorities in their investigation."
Mountaire Farms said authorities have inspected the plant and declared the building safe. The plant is expected to reopen and return to full operation on Monday.
The Lumber Bridge factory was formerly owned by Piedmont Poultry, but Mountaire Farm purchased the branch location in 1996.
According to the Millsboro, Del.-based company's Web site, three years after the purchase they doubled the production at the poultry processing plant.
This is the second time this month a North Carolina food processing factory has faced tragedy. Almost three weeks ago, three employees at the ConAgra Foods plant were killed and dozens of others injured after a natural gas explosion.