The United States transferred 35 detainees from the US naval base prison in Guantanamo Bay, Cuba, to Pakistan on Saturday, bringing to 191 the number of detainees having departed Guantanamo, the Pentagon announced.

Of the 35 detainees, 29 were handed over to Pakistan for continued detention and six for release.

The transfer included the one detainee who was approved for release by the Defense Department after the Combatant Status Review Tribunal found that he was not an "enemy combatant."

The decision to transfer or release a detainee was based on many factors, including whether the detainee was of further intelligence value to the United States and whether the detainee was believed to pose a threat to the United States if released, the Pentagon said in a press release.

Previously, the United States had transferred 129 detainees for release and 27 others for continued detention by their respective governments.

With Saturday's transfer, approximately 550 detainees from about 40 countries are still being held at Guantanamo, most of whom have been held there without charges or access to a lawyer for about two and a half years.