Afghanistan is to release 88 prisoners even though the US considers them dangerous and wants them to remain in detention, the board reviewing their cases has said.
The prisoners are being held at a jail at the Bagram airbase, north of Kabul. The US only recently transferred the prison to Afghan control after it had become a serious source of tension with the government.
President Hamid Karzai instructed Afghan intelligence officials to provide the review board with more evidence against the prisoners, after the US said there was proof of their involvement in the killing of foreign troops and they posed a serious threat to security.
But the head of the review board, Abdul Shakor Dadras, said the evidence did not warrant keeping the prisoners any longer. "The documents we have seen so far provide no reason to convict them," Dadras said on Sunday.
"Our decision is to release them as soon as possible if there is no incriminating evidence against them."
The disagreement over the prisoners is a further strain on Afghan-US relations, already seriously soured by Karzai's refusal to sign a bilateral security deal to shape the American military presence after most foreign troops leave this year.