Karachi- Pakistan International Airlines (PIA) spokesman Mashhood Tajwar said that some 15 to 20 flights were affected due to Karachi airport attack and added that the restoration of the flight operation would take sometime after security clearance. Talking to Private TV, Mashhood Tajwar said that according to civil aviation officials the clearance operation at the Karachi airport was expected to continue until 12 noon today Local and foreign flights were suspended including those for Lahore, Islamabad and Peshawar. Passengers have been advised to contact PIA enquiry office before leaving for the airport to catch their booked flights, he said.