Bagram releases worsen US-Afghan ties
The release of 65 men from a detention centre at Bagram had been criticised in unusually strong terms by the US in Afghanistan for months before it finally happened.
They say the men are "dangerous insurgents", and the Afghan authorities never seriously considered the evidence.
US forces say this violated the terms of an agreement for the US to hand over full control of the detention centre to Afghanistan.
All of the men released have been detained since the agreement was reached in September 2012.
US forces have distributed detailed information on the men. Almost half were detained in Helmand, the province where British forces have been fighting since 2006.
One of the men was captured after being wounded during an attack on Afghan forces. Others were arrested carrying weapons including shotguns, assault rifles and rocket-propelled-grenade-launchers.
The US dossier also includes incriminating information from mobile phones, details of interviews with suspects including confessions, and pictures of bomb-making equipment. Most of those about to be released tested positive for explosive residue on their hands and clothing.
This is one of the most contentious issues between the two countries.
The Bagram detention centre was originally set up by US troops in a former Russian aircraft hangar.
The legal status of those being held was never clear, and there were frequent allegations of torture made against US soldiers.
After the 2012 deal, it took several months of legal arguments before the Afghan authorities finally took full control of the detention centre in March 2013, now in a new building.
Around 3,000 prisoners were handed over, and since then hundreds have been released after the evidence against them was assessed by an Afghan review process. Many have been prosecuted in a special court set up at the detention centre.
Those were mostly cases where there was very little evidence. But the releases are now becoming more complicated as the easy cases have been dealt with.
Along with the 65 now released, there are still believed to be around 70 prisoners in Bagram who have the status of EST - Enduring Security Threat.
They were given this description by the US before they handed over the jail. There would be strong American protests if they were released.
But US attempts to prevent this week's release have failed. They say that the cases were "never seriously considered, including by the attorney general".
'Taliban training camp'
The suspicion is the decision to release the men was political and not legal, and was taken by President Karzai himself.
Now in his last months in office, he has taken a stridently anti-US line in several recent TV interviews, and refused to sign a deal to allow US troops to remain beyond the end of 2014, despite it being approved by Afghanistan's highest representative authority - a loya jirga.
But the story of the Bagram facility is not simple. President Karzai is not alone in believing that its large shared cells are a 'Taliban training camp', where common prisoners face radicalisation by insurgents.
A further complication is the presence of approximately 60 detainees from other countries. They are held in a corner of the facility that is still controlled by US troops, with the same unclear legal status as those in Guantanamo Bay.
But unlike Guantanamo Bay, there is a deadline for holding the foreign nationals in Bagram.
There may be no US troops in Afghanistan beyond the end of 2014, and Chris Rogers, from the Open Society Foundations, said "it is just a matter of time before this becomes a serious issue".
There have been negotiations to resolve the issue, but Mr Rogers said that it was hard to see how they were going to meet the deadline.
Most of the foreign detainees are from Pakistan, but when a small number were released before, they were promptly detained there.