Islamabad, PAKISTAN: At least 10 prisoners being held by US forces at Afghanistan’s Bagram prison have been released into Pakistani custody, the International Committee of the Red Cross (ICRC) has told the prisoners’ families.

The prisoners have been repatriated to Pakistan, but their whereabouts remain unknown, the lawyers representing the families told Al Jazeera.

The 10 prisoners released are Awal Noor, Bismillah Khan, Iftikhar Ahmed, Paizoo Khan, Farman Shah, Abdul Sattar, Shah Khalid, Wajid Rehman, Rehmatullah and Sallah Muhammad (also known as Yunus Rehmatullah), according to a statement released by the Justice Project Pakistan (JPP), who represent the families.

As far as we are concerned legally they were being held without charge. Sarah Belal, Justice Project Pakistan

"All have been held for several years without charge and access to a lawyer,” the JPP statement said.

The Pakistani Foreign Office confirmed the prisoner release, but was unable to provide details regarding the mechanism by which it occurred, or what the men had been charged with.

Tasneem Aslam, a spokesperson for the Foreign Office, told Al Jazeera the release was "expected", and that approximately 20 Pakistanis remained in US custody at the Bagram facility.

"The process for the confirmation of nationality for the rest of the people is under way and […] the Americans are also very keen that before they close down the facility and hand it over to the Afghan government that the process can be completed," she said.

US forces, who operate the facility at Bagram, are due to hand over the prison to Afghan authorities by December 2014, as part of their withdrawal from that country.

Sarah Belal, lead counsel for JPP, said that the families were still seeking information on what charges the men had been held.

"There's never been a charge sheet that has been produced by the Americans or the Pakistani government. As far as we are concerned legally they were being held without charge," she said, adding that her organisation, which has been contesting a case related to these detainees at the Lahore High Court, would be seeking the court’s intervention to produce the prisoners.

In November 2013, six Pakistanis were released from US custody at the Bagram facility and handed over to Pakistani authorities. They were then held by authorities for 10 days, before being released to return home.

"We are going to court tomorrow, because the Pakistani government is again in breach of their duty," said Belal. "They haven't informed the court or the families or the legal representatives about [the prisoners’] repatriation and location in Pakistan."

Pakistan’s interior ministry, which has handled such releases in the past, did not respond to a request for comment.

Yunus Rehmatullah, one of those released, was originally captured by the British military in Iraq in 2004, before being transferred into US custody at Bagram, according to UK-based rights group Reprieve.

In 2012, the UK’s Supreme Court ruled that Rehmatullah’s rendition was a breach of the Geneva Convention, and that his detention was “unlawful”.

Kat Craig, legal director at Reprieve, said: “After ten years of unimaginable abuse and imprisonment at the hands the British and US forces, Yunus Rahmatullah deserves a full investigation into the circumstances of his capture. He must receive justice, so that he and his family can move on and return to some semblance of their old, peaceful life.”

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