Fire investigators will head to a large abattoir east of Adelaide to try to determine the cause of a major blaze that engulfed the facility.
Investigators are expected on site on Thursday morning to begin their work at the Thomas Foods International operations at Northern Heights near Murray Bridge.
The blaze, which broke out at about 7pm on Wednesday, has caused major damage but police say there have no injuries.
The company has reported that all workers were evacuated safely.
The plant has a workforce of about 1400 but it's unclear how many were on site at the time.
At the height of the fire, the Metropolitan Fire Service said part of the structure had collapsed as about 100 firefighters battled the flames.
They pumped water from a nearby lagoon in their efforts to bring the blaze under control.
Local residents were being told to keep doors and windows closed because of smoke drifting across nearby homes.
MFS and Country Fire Service crews remained on the scene throughout the night with police enforcing road closures in the immediate area.
Thomas Foods International is Australia's largest, family-owned meat processing company, which has annual revenue of more than $1 billion.
It operates another processing plant at Lobethal, in the Adelaide Hills, and also has operations at Tamworth in NSW and at Wallangarra in Queensland.
The company said it was making alternative processing arrangements to meet the needs of its customers.