KARACHI   - The Airport Security Force foiled a bid to smuggle 2-kg heroin here on Tuesday. According to custom officials, the ASF during clearance of a plane at Quaid-e-Azam International Airport, found 2-kg heroin in the plane. The custom officials said that the drug was being smuggled to abroad and was worth millions of rupees in international market. A case has been registered against unknown culprits and investigation has been started.