By Martin Patience
BBC News, Kabul
A child talks on the video-phone to his father in the Bagram detention centre
The last time Mohammed Ali spent time with his older brother Ashraf, 38, was in a cell and he did not know if it was "night or day".
The brothers were arrested by US forces in their small village in Kunar province, eastern Afghanistan, 16 months ago.
He says the door of their shared house was blown up in the early hours of the morning, then they were handcuffed and taken away in a military helicopter.
Mohammed, 35, was freed after three and a half weeks. He has no idea where he was held. Ashraf, 38, has been in detention ever since.
"They accused us of belonging to the Taleban," said Mohammed, explaining why the brothers had been arrested. "But they are wrong. The Americans were fed lies by spies in our village."
Ashraf, a father of six, is one of around 630 Afghan detainees held at Bagram airport, a US military camp located 60 km (35 miles) from the capital, Kabul.
The US military considers the men "unlawful combatants" who can be detained for as long as they are deemed a threat to Afghan national security.
In the past, some prisoners have been transferred to local jails where they are processed through the Afghan justice system.
Detainees at Bagram have faced harsh interrogations at the prison. In 2002, two Afghan detainees died after being repeatedly struck by American personnel.
Families of many of the detained men say that initially they had no idea where their relatives were being held, and then had only sporadic communication by letters delivered by the International Committee of the Red Cross (ICRC).
But since the start of the year, the Red Cross - in co-operation with the US military - has been running a new programme.
Families now have access to weekly video-conference calls which allow them to speak to - and see - their detained relatives.
The phone calls can be emotional experiences
The project has been a remarkable success, with almost 70% of the prisoners in Bagram having received a video call in the last four months, according to the Red Cross.
Last week, Mohammed, along with around 50 other Afghan men, gathered at the Red Cross compound in Kabul to register for the video-conference call the following day.
For Mohammed, a school teacher, the 20-minute call means a three-day trip away from his village.
It was his third trip. This time he was accompanied by four other members of the family, including an aunt and his grandfather.
"Everyone, Ashraf's children, my children, all of us want to see him," said Mohammed. "But only five people are allowed to visit, so only five of us have come."
'Intensity and emotion'
The Red Cross is keen to point out that the programme is no substitute for actual prison visits - something that has not been allowed until now.
Prisoners can be held at Bagram for indefinite periods
"There's nothing that can replace the intensity and emotion of face-to-face visits," said Graziella Leite Piccolo, a spokeswoman for the organisation.
"We continue reminding the American authorities of the relevance and importance of these visits."
On the day of the video-conference calls, families jostled at the Red Cross compound with anticipation.
One young boy came out of the video-conference room with tears streaming down his face after taking part in a call.
For many this is the first time in months, if not years, that they have seen their loved ones.
At Mohammed and his family's allotted time, they crammed into a cubicle to speak to his brother.
The faces of other families in the room lit up as they saw their loved ones on the screen. They jostled to hand the telephone to each other and whisper a quick word to their relation.
After the call, Mohammed's grandfather, Zahir, said that Ashraf appeared in good spirits.
"I told him that I would stay in jail so that they would allow him to go home and see the family," said Zahir, a wide smile breaking across his face. "He was delighted to hear this."
Mohammed said that despite the difficulty of his brother's detention the family would not lose hope.
He said that the family count "the night and days" and desperately wait for Ashraf's return.
"When he doesn't appear then we say to ourselves 'okay, he will come tomorrow morning'," he said.
"We keep doing this, but we understand that nobody knows when he will be released. But we are hopeful that he will come back one day."