Islamabad, Aug 25 (Reporter) Two troops were killed, and seven others injured in a clash with militants in Pakistan's northwest Khyber Pakhtunkhwa province on Sunday, police sources said. The incident happened at about 12:20 local time (0720 GMT) in the Tirah Valley area of the Khyber district, where both sides engaged in an exchange of fire, the sources told Xinhua. The injured, including a captain, were initially shifted to a nearby hospital from where they had been airlifted to the provincial capital city of Peshawar, the sources added. The identities of the attackers or their affiliation with any terrorist group had not been revealed...////...