BOISE, Idaho — The surveillance video from the overhead cameras shows Hanni Elabed being beaten by a fellow inmate in an Idaho prison, managing to bang on a prison guard station window, pleading for help. Behind the glass, correctional officers watch, but no one intervenes as Elabed is stomped on a dozen times and knocked unconscious.

No one steps into the cellblock when the attacker sits down to rest, and no one stops him when he resumes the beating.

Videos of the attack obtained by The Associated Press show officers watching the beating for several minutes. The footage is a key piece of evidence for critics who claim the privately run Idaho Correctional Center uses inmate-on-inmate violence to force prisoners to snitch on their cellmates or risk being moved to extremely violent units.

On Tuesday, hours after the AP published the video, the top federal prosecutor in Idaho told the AP that the FBI has been investigating whether guards violated the civil rights of inmates at the prison, which is run by the Corrections Corporation of America. The investigation concerns the prison’s rate of violence and covers multiple assaults between inmates, including the attack on Elabed, said U.S. Attorney Wendy Olson.

CCA spokesman Steve Owen said the company is cooperating with federal agents, as it has with other law enforcement overseeing the prisons. The nation’s largest private prison company also said it was “highly disappointed and deeply concerned” over AP’s decision to release the videos.

Lawsuits from inmates contend the company denies prisoners medical treatment as a way of covering up the assaults. They have dubbed the Idaho lockup “gladiator school” because it is so violent.

Violence behind bars and misconduct by guards is common, regardless of whether prisons are run by the government or private companies. CCA, which oversees some 75,000 inmates in more than 60 facilities under contracts with the federal government, 19 states and the District of Columbia, is no exception.

A year ago, CCA and another company, Dominion Correctional Services LLC, agreed to pay $1.3 million to settle a lawsuit in which the Equal Opportunity Employment Commission claimed male officers at a prison in Colorado forced female workers to perform sex acts to keep their jobs.

In January, Kentucky Gov. Steve Beshear ordered some 400 female inmates transferred to a state-run prison after more than a dozen reports of sexual misconduct by male guards employed by CCA. Similar accusations were made in March at a CCA-run prison in Hawaii, and in May, agents with Immigration and Customs Enforcement placed CCA on probation and launched an investigation into whether a guard at a central Texas detention facility sexually assaulted women on their way to being deported.

Olson said the FBI investigation is focused solely on the Idaho prison and not any of the other prisons operated by CCA.

Before the Idaho attack, Elabed tried to get help from prison staffers, telling them that he had been threatened and giving them details about drug trafficking between inmates and staffers that he had witnessed, according to his lawsuit. He was put in solitary confinement for his protection but was later returned to the same unit with the inmates he snitched on, his lawsuit said.

Elabed was on the cellblock only six minutes before he was attacked. He bled inside his skull, spent three days in a coma and still suffers from the after-effects of his injuries.

Steven Pevar, an attorney for the American Civil Liberties Union, said in 34 years of suing more than 100 prisons and jails, the Idaho lockup is the most violent he has seen.

“This isn’t even what we know of as a prison – this is a gulag,” Pevar said.