At least 13 people were killed and 16 others injured in a fresh wave of violence triggered by the killing of a local party official in Karachi, a privat TV reported on Friday. According to the report, the riots broke out on Thursday after the Awami National Party (ANP) office bearer, Ubaidullah Yousufzai, was gunned down along with a colleague near the QuaideAzam International Airport. In the subsequent violence, 11 people were shot dead and 16 others were injured while 12 vehicles were set on fire by miscreants, the report said. In early August, the assassination of a local party MQM leader virtually turned Karachi into a slaughterhouse, where target killings took place almost on a daily basis for a weeklong time, during which nearly one hundred people were killed while many shops and vehicles were burnt. The rampant target killings mainly resulting from the partisan struggle between ANP and MQM, two major rival parties in the country, did not come to a respite until a truce agreement was reached under the intermediation of the Pakistani prime minister Gilani.