Three people were killed and about a dozen injured in an explosion in a residential colony near Sivli Road under Kalyanpur Police station area of Kanpur on Thursday afternoon.The DIG police of Kanpur Prem Prakash told AIR correspondent that 12 people including eight children have been rescued from the debris of the two storyed house which was damaged in the blast. He said that condition of four persons is serious. According to DIG Police, exact cause of the explosion is being investigated. But initial reports indicate that the some fire crackers or crude bombs were stored or being manufactured when the explosion occurred. Intelligence teams have reached the spot to investigate the incidentMeanwhile IG police of Kanpur G L Meena told AIR that Relief and rescue operations are on and senior administrative and police officers have reached the spot .