HANFORD, Kings County (CBS/AP) — Federal investigators probing a Central Valley slaughterhouse say none of the sick cows that were videotaped being mistreated there entered the food supply.

A spokesman for the U.S. Department of Agriculture says a team of investigators dispatched to the Central Valley Meat Co. in Hanford reached that conclusion on Friday.

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The USDA closed the plant for a week after an undercover video shot by the group Compassion Over Killing showed downed animals being repeatedly kicked, shocked, shot and pulled by the tails by workers trying to get them to stand.

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Food Safety Inspection Service Administrator Al Almanza says the investigators concluded that no food safety violation had occurred.

But the investigators continue to probe the allegations of inhumane treatment.

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