islamabad - Pakistan Tehreek-e-Insaf announced on Saturday that the party has cancelled its public rally in Karachi scheduled for May 1 citing security concerns. PTI Chairman Imran Khan was scheduled to address the rally. A PTI spokesman said the rally had been cancelled due to worsening law and order situation. The rally, however, had been shifted to Sukkur on May 1, the spokesman added. Karachi has seen three major terrorist attacks targeting MQM and ANP this week in which over a dozen people died.