Fire investigators are working to determine the cause of a massive fire that tore through three pig barns in rural Manitoba on Friday afternoon, killing an estimated 7,500 animals.

The fire broke out around 1 p.m. CT in the Rural Municipality of La Broquerie, south of Steinbach.

Officials say the first firefighters on the scene were confronted with a major blaze.

"They immediately called for assistance and a total of four fire departments attended for suppression purposes," Rick Vandekerkhove, a spokesman for Manitoba's fire commissioner, told CBC News on Saturday.

"Unfortunately it was a total loss of livestock within the barns."

Vandekerkhove said the cause of the fire was still under investigation. No people were injured in the fire.

It was the second devastating fire to strike an agricultural operation in the area in less than week.

On Monday, around 450 cows were killed in a fire at a dairy farm in the Rural Municipality of Ste. Anne, also in southeastern Manitoba.