In Pakistan, at least four factory workers were killed today when unidentified men threw hand grenade at their vehicle in the southern Balochistan province. Police said the employees of a cement factory were heading to Karachi after finishing work when they came under hand grenade attack at the town of Hub. <br/><br/>The attacked also injured five other people. No group claimed responsibility for the attack. Motives behind the attack were unclear but police say that it may be incident of target killings.<br/>