RSS leader Indresh Kumar has hit out at the National Investigative Agency which yesterday arrested Kamal Chauhan for the 2007 Samjhauta Express blast.Kumar questioned whether the NIA's job was to investigate the blast or create propoganda against the RSS. He termed it a planned conspiracy by the NIA against the RSS, saying the agency randomly named accused. Kamal Chauhan, a disgruntled former RSS worker arrested by the NIA claimed that he had planted bombs on board the Samjhauta Express in 2007.Meanwhile congress Gen Secy Digvijay Singh lashes out at RSS leaders over the Samjhauta blast probe.