The US Secretary of Defence Leon Panetta has claimed that al-Qaida chief Dr Aiman-al-Zawahiri was hiding in Pakistans tribal region.
Panetta who arrived in Afghanistan on Saturday on a surprise-maiden visit, was of the view that pressure will be mounted on Pakistan to kill Zawahiri.
He added that 20 top commanders of al-Qaeda, might be living in Somalia, Pakistan, Yemen and North Africa will be killed or arrested after Osama.
Panetta said Pakistan has rendered great sacrifices in war against terrorism.