They say the message was recorded last week somewhere in the area around the border between the tribal agency of Bajaur in Pakistan and the province of Kunar in Afghanistan.
According to their intelligence, the message is currently being digitalized and "passed around" in the Pakistani city of Peshawar, from where, they say, it will be "uploaded" to one of the jihadi websites which have been used to spread such material in the past.
THE BLOTTER RECOMMENDS
The hunt for the couriers, messengers or computer scientists involved in the logistical chain between al Qaeda's leaders and the media is at the heart of Pakistan's efforts to track down Osama Bin Laden and Ayman al Zawahiri.
It is through one of these couriers, who was caught in 2005, that they were able to locate and arrest al Qaeda's "No. 3," Abu Faraj al Libbi, who was wanted in Pakistan for masterminding the assassination attempts on President Musharraf.
Pakistani intelligence sources told ABC News in August that they had "very good intelligence on the whereabouts of Ayman al Zawahiri" and were "reasonably confident" that they would be able to catch him in the next few months.