All staff at a large South Australian abattoir east of Adelaide are safe after a fire engulfed the facility.
About 100 firefighters continued to battle the blaze late on Wednesday at the Thomas Foods International facility at Northern Heights near Murray Bridge.
The Metropolitan Fire Service said a building had started to collapse and livestock were being moved as efforts continued to bring the blaze under control.
The MFS said firefighters had to use defensive strategies against the flames after a partial structure collapse, with water being pumped from a nearby lagoon.
Management had also started moving livestock to safer ground.
In a statement, the company said the cause of the fire and the full extent of the damage were yet to be determined.
"Thankfully all our employees on site were safely and promptly evacuated," the statement said.
The company said it was making alternative processing arrangements to meet the needs of its customers.
The abattoir has a workforce of about 1400 but it was unclear how many were on site when the fire broke out.
The public were asked to avoid the area and a smoke advice alert was in place for nearby suburbs.
Local residents were being told to keep doors and windows closed.
"The emergency is causing smoke to drift across Northern Heights and surrounding suburbs," an advice alert said.
The Labor candidate for the local seat of Hammond Mat O'Brien said he was "in my yard watching in disbelief as Thomas Foods is ablaze".
"No reports of injuries but my thoughts are with employees and families of Murray Bridge's largest employer as they face uncertain times," he tweeted.
Thomas Foods International is Australia's largest, family-owned meat processing company, which has annual revenue in excess of $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.