North Shore Animal League America is one of the biggest and most well-known animal shelters in the country. However, there are multiple allegations that the organization has put dogs up for adoption without providing details about their dangerous pasts.

Lauren McCarthy was attacked by her dog, a 7-year-old black lab mix named Ringo.

“He just lunged and started shaking my arm…All my flesh was pulled back, I was bleeding profusely all over the street,” said McCarthy.

McCarthy says the terrifying incident happened back in May of 2017, about one month after she adopted Ringo from the North Shore Animal League in Port Washington.

In the paperwork McCarthy says she received from North Shore, Ringo was described as a playful, puppy-like dog. But documents given to News 12 by former North Shore Animal League employees paint a different picture.

The whistleblowers say the reports and evaluations are internal documents not released to the public. They show that Ringo bit workers or volunteers at the shelter three times, sending one to the hospital about seven months before he was adopted.

McCarthy says nobody at North Shore ever told her about those attacks.

News 12’s investigation also found several similar cases.

Records from the whistleblowers show a German shepherd mix named Kobe bit multiple people, including an 81-year-old woman who needed 30 stitches. Despite this, the dog was adopted or fostered several times. There was no mention of any previous attacks in the paperwork that News 12’s whistleblowers say were given to clients.

When contacted by News 12, one of those clients said North Shore never told him the dog had bitten anyone.  In another case, a different client said the shelter kept quiet about the elderly woman's 30 stiches and hospitalization. The client said North Shore downplayed the seriousness of the incident, telling them Kobe accidentally bit her while he was trying to get food from the kitchen counter.

Lastly, there's a dachshund named Cary Grant. According to documents, that dog attacked his owner three years ago. As of March 2, Cary Grant is on the Animal League's website and available to be adopted. The ad says Cary Grant has what they call "special needs,” but it makes no mention of a dangerous past. It even says he'd be a good fit for a family with kids ages 12 and up.

Former North Shore Animal League employees Gia Savocchi and John Bishow-Semevolos say they were directed by their superiors to hide the biting history of animals and use euphemisms instead -- phrases like "resource guarding" -- which means a dog protects its food or possessions.

Gary Rogers is a detective with the Nassau SPCA and one of the county's best known animal advocates. He says failure to disclose an animal's full history puts both the dog and its owner at risk.

News 12 tried multiple times to interview someone on camera at the North Shore Animal League. The investigative team also gave North Shore Animal League the names of the dogs on the paperwork. However, nobody from the organization would agree to meet with News 12.

The shelter did send News 12 a statement saying, "Dogs with a known bite history are monitored and receive behavior modification from our Pet Behavior team... if any of these dogs are being considered for adoption, our team counsels the potential adopter to determine whether or not the dog would be the appropriate match for the adopter and their circumstances. During this process, the dog's full behavior history is disclosed and reviewed -- verbally and in a written document -- with the potential adopter."

But Lauren McCarthy says nobody told her about Ringo's biting history – either verbally or in writing.

McCarthy tells News 12 that omission nearly resulted in permanent nerve damage to her right arm. But the most painful part of the story, she says, is that Ringo was put to sleep. McCarthy says it could have been avoided if the shelter was honest about the dog's past.