At least 29 people were killed in different firing incidents in Karachi on Thursday, taking death toll of the political and ethnic violence in the city to 65 in the last three days, reported local media. According to the local media reports, at least 13 people were killed on Thursday afternoon when unknown gunmen fired at two buses in the city. Some 30 others were also injured in the attack. Parts of Karachi had been tense the whole day on Thursday and most of petrol stations remained closed over security concerns. Long queues of cars and motorcycles were seen in front of open petrol stations in the city. Government and private ambulance service had been busy to transfer the dead and injured to hospitals. According to the local media reports, there had been grenade attacks on houses and shops, forcing the people to move to safe places.