GRAPHIC: Hidden camera reveals abuse of pigs at Oklahoma farm

HENRYETTA, Okla. – The animal welfare group Mercy For Animals has released undercover video from an Oklahoma pig farm that shows shocking abuse of animals.

They say over a three-week period, an undercover employee taped other workers at West Coast Farms slamming piglets to the ground, gouging their eyes and cutting off their tails.

They say pregnant pigs are tortured by being confined to tiny gestation crates.

Mercy For Animals is calling on Walmart to immediately prohibit Tyson Foods, which receives pork from that farm, from confining pigs so that they cannot even turn around.

NBC News received a response from Tyson.

“We’re extremely disappointed by the mistreatment shown in the video and will not tolerate this kind of animal mishandling,” Gary Mickelson said, a spokesman for Tyson Foods. “We are immediately terminating our contract with this farmer and will take possession of the animals remaining on the farm.”