The BBC has heard claims by 27 former detainees of the US Bagram base in Afghanistan that they were abused at the facility, through methods including beatings, sleep deprivation and death threats.
Afghan and US officials have been giving their reactions to the allegations.
SPOKESMAN FOR AFGHAN PRESIDENT HAMID KARZAI
Mr Hamidzada said similar allegations about the mistreatment of prisoners at the Bagram base had been heard before.
He said that if there were any substance to the accusations they should be investigated further.
"Any inhumane act, torture or anything else that is against the Afghan constitution should not happen," he said.
But he said that, as the detainees were not in Afghan custody at the time the alleged abuse took place, "their complaints are against the international forces".
Mr Hamidzada said the Afghan government wanted all prisoners held at Bagram handed over to their custody, so those who had committed crimes could be dealt with by the judiciary while the rest could be freed.
US CHARGE D'AFFAIRES IN LONDON
"The Bagram facility is operating in a warzone - even there we've had attacks, we've lost soldiers from Taliban attacks just in the last few days. We're operating under the rules of law and we're operating in a very active warzone.
"As President [Barack] Obama has said, we are committed to humane treatment of all detainees wherever they may be and we are going to keep to that pledge.
"There are also processes in Bagram for reviewing the status of combatants: as they come into the facility, 90 days after they are there and again after six months. So there is an active review to make sure that people are not being held for any illegitimate reasons.
"When there are allegations of abuse we investigate them and we hold people responsible. We hold people to a very high standard. President Obama has made that crystal clear and people need to know that.
"I have no way to give any credibility to [the BBC's] report. I have no way to judge its credibility. I don't know if these 27 people have talked to each other before, I don't know where they came from, I don't even know if they were actual detainees. So I can't answer for those particular people, but as a matter of policy we do look into all allegations of abuse."