CHICAGO (CBS) — Two days after the release of a disturbing video showing workers abusing calves at Fair Oaks Farms, the animal rights group that recorded the footage has provided an extended version of the undercover video.

“The extreme and systematic abuse gone viral has the public outraged,” Animal Recovery Mission said of the video its investigators filmed after going undercover at Fair Oaks Farms last year.

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On Wednesday, the nonprofit animal rights group released a 12-minute video showing workers dragging calves by their ears, throwing calves into small plastic isolation hutches, hitting calves with milk bottles, kicking calves, beating them with branding irons and steel rebar, and force-feeding the animals to the point they can’t breathe. Workers are also seen piling dead calves onto farm vehicles and throwing them in mass dump sites and keeping them in filthy conditions and forcing them to endure extreme heat in isolation pens.

On Friday, Animal Recovery Mission released a 90-minute video showing the abuses at Fair Oaks in greater detail.

“The purpose of this hour and half long video detailing the extreme violence at Fair Oaks Farms, is to give the greater public an in-depth insight into the sheer gravity of animal abuse that takes place in the dairy industry. The extended video also shines a light into the drug use, as well as giving a detail look into top management’s knowledge of the brutally on the calves and zero action taken upon the abusers and or aiding in the neglect of the baby animals,” Animal Recovery Mission founder Richard Couto said in a statement.

Fair Oaks said the plants shown in the video are not marijuana but native wild plants common in the area.

ARM has said it had an undercover investigator get a job at Fair Oaks Farms from August to November of last year in order to expose animal cruelty.

The new video starts with footage of a calf lying in a plastic hutch and text on the screen claiming a Fair Oaks manager had shot the calf and left it to die even though it was moving and suffering for hours.

Animal Recovery Mission has said the abuse took place in open view of Fair Oaks managers and claims supervisors and owners at Fair Oaks were aware of and even took part in the acts of animal cruelty.

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In a Facebook post in April, Fair Oaks Farms acknowledged that a group had “infiltrated” its farms.

At the time, Fair Oaks believed the goal of the undercover operation was “not to share a fair and balanced view of animal welfare, but to specifically and misleadingly create animal cruelty videos.”

Fair Oaks acknowledged that it had fired three employees even before the video was made public. A fourth was fired after the video was made public.

Fair Oaks Farms has said five individuals were identified from the video, four of them Fair Oaks employees and the fifth a third-party truck driver who was picking up calves. The company said three of the four employees were fired before the video was released after co-workers caught them abusing animals and reported them to management. The fourth was fired on Tuesday after the ARM video was released.

“Watching this video broke my heart and created a sadness that I’ll have to endure the rest of my life,” Fair Oaks founder Dr. Mike McCloskey said in a video posted on Facebook on Thursday before the release of the longer video. “I am sorry, and I apologize for the footage in this video.”

McCloskey, who is a veterinarian, said all of the farm’s workers receive training on animal welfare and sign an agreement to immediately report any acts of animal cruelty to a supervisor. In response to the video, McCloskey said he will install cameras anywhere on the farms where workers are interacting with animals and will implement more thorough training and monitoring for employees.

At least four grocery store chains – Jewel-Osco, Strack & Van TIl, Family Express, and Tony’s Fresh Market – have pulled all Fairlife dairy products from their shelves in response to the video. Fairlife is owned by McCloskey and gets its dairy from Fair Oaks Farms.

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The Newton County Sheriff’s Office has launched an investigation of Fair Oaks Farms, and McCloskey has said he would work with the Newton County Prosecutor’s Office and the Indiana Attorney General’s office to review the video and prosecute anyone responsible for abusing animals.