The letter, sent Tuesday, gives Midwestern 15 working days to write back with word of steps it took to fix the violations found during the inspections.

(CBS) — The Food and Drug Administration has issued a warning letter to Midwestern Pet Foods after possible links were found between its products and the deaths of 130 dogs and illnesses in 220 others.

The agency says it sent the letter after inspections of Midwestern’s plants discovered “apparent violations” of federal law “that were shared across the sites.” These conditions likely contributed to the illness or death of hundreds of dogs who had eaten Midwestern’s dry dog food.

READ MORE: Pet Food Recall Expanded Due To Toxic Levels Of Aflatoxin

“We acknowledge your voluntary recalls of adulterated product contaminated with aflatoxin and Salmonella. However, recalling product does not prevent the reoccurrence of a hazard in your pet food,” according to the letter.

An earlier inspection found that one Midwestern brand, Sportmix, had high levels of aflatoxin, or a toxic mold that can grow on grains, the FDA said. The symptoms of aflatoxin poisoning including sluggishness, loss of appetite, vomiting, jaundice and diarrhea.

READ MORE: Pet Food Recalled Again, This Time Over Salmonella Risk

Evansville, Indiana-based Midwestern launched voluntary recalls in January and March due to issues with mold and salmonella.

The letter, sent Tuesday, gives Midwestern 15 working days to write back with word of steps it took to fix the violations found during the inspections.

To read the full letter from the FDA to Midwestern Pet Foods, visit this link.

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