At least six people including a woman and child were killed when a mortar shell exploded in northern Pakistani tribal area bordering Afghanistan on Wednesday, said officials.According to security officials, the explosion took place in a house of Shawal area of North Waziristan tribal region killing at least six people including a woman and child.The blast occurred as a mortar shell placed in the house exploded suddenly, said officials. The security forces reached the scene and a probe went underway.Meanwhile, a planted bomb exploded injuring at least five people including a woman near the Sirki Gate area of the northwestern Peshawar city of Khyber Pakhtunkhwa province. According to the Bomb Disposal Squad (BDS) personnel, at least half a kilogram of explosive material was used in the bomb.The blast occurred as the Pakistan government and banned outfit Tehreek e Taliban Pakistan (TTP) were undergoing a peace dialogue process to end the ongoing insurgency and militancy in northern province and tribal areas.