McDonald's has dropped a Minnesota-based egg supplier after an animal rights group released an undercover video of operations at the egg producer's farms in three states.

The video by Mercy for Animals shows what it calls animal cruelty, including a worker swinging a bird around by its feet.

McDonald's Corp. said Friday the behavior on the video is "disturbing and completely unacceptable." The fast food chain says it demands humane treatment of animals by suppliers.

The move follows a warning letter to Sparboe Farms this week from the Food and Drug Administration saying inspectors found serious food safety violations at five Sparboe facilities.

A Sparboe Companies LLC spokesman says the company has a "zero tolerance policy" for animal abuse or cruelty.

The three states affected are: Minnesota, Iowa and Colorado.

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