Editor's note: Note graphic content.
(CNN) -- Videos purportedly showing guards abusing prisoners, including one male inmate being raped with a broom handle, have led to arrests and outrage both inside and outside the Eurasian country of Georgia.
President Mikheil Saakashvili said Wednesday what occurred at Gldani Number 8 penitentiary in Tbilisi is "a horrific affront to human rights and human dignity."
Georgia television stations, including TV9, broadcast the videos Tuesday night. The government has not questioned their authenticity.
"The police have already arrested most of those identified as involved in these gross abuses," Saakashvili said in a statement. "Others are on the run but (are) being actively pursued by police."
The faces of those being filmed were obscured. One man cries out while he is being raped with a broom handle. Another video shows an inmate being punched.
The country's interior ministry on Tuesday blamed certain prison employees for the degrading treatment.
The ministry said a prisoner at the facility offered "substantial reimbursement" to employees for their actions and the video recordings. Its statement did not elaborate on the prisoner's motivation.
The interior ministry identified that prisoner as Tamaz Tamazashvili, father-in-law of Irlakli Garibashvili, a member of the opposition Georgian Dream party.
Garibashvili said Tamazashvili's life was in danger and that he was being held "hostage" by the president.
Tamazashvili had nothing to do with the taped incidents, Garibashvili said.
Georgia's minister of corrections and legal assistance, meanwhile, tendered her resignation.
"During my time in the office I tried my best and did everything possible to ensure the protection of human rights and to bring the corrections system, as much as possible, in conformity with the European standards," Khatuna Kalmakhelidze said in a statement. "It seems, however, that this effort was not enough, since such facts have taken place. I am very sorry about what happened and it does not matter who orchestrated these events."
Human Rights Watch said Gldani Number 8 has been referred to as one of Georgia's "most problematic prison facilities."
"The abuse captured in this footage is profoundly disturbing," said Giorgi Gogia, senior Europe and Central Asia researcher for the organization. "The authorities need to ensure full accountability -- including criminal accountability -- for this abuse and take measures to prevent it from ever happening again."
Victims of the abuse are entitled to legal remedies, according to Human Rights Watch.
"Sexual assault on a detainee constitutes torture," Gogia said in a statement. "The prohibition on torture is absolute, and the government should ensure that the justice is done."
The U.S. Embassy in Georgia said it was shocked and revolted by the images and noted the government's investigation.
"Abuse of prisoners is a serious issue that needs to be addressed," the embassy said in a statement issued Wednesday. "We urge that the government conduct this investigation in a thorough and transparent manner and ensure that all those responsible are brought to justice as soon as possible."
CNN's Alex Felton, Nunu Japaridze and Jack Maddox contributed to this report.