Congress leader Digvijaya Singh, who has kicked up a storm over his remarks on slain Maharashtra ATS chief Hement Karkare, killed in the Mumbai attacks, took on the Opposition. "Advaniji, Ravishankarji and Rajnath Singh should first answer as to why they had called Hemant Karkare ji a traitor? They should answer as to why Advaniji led a delegation to the Prime Minister in support of Pragya Thakur and Dayanand Pandey," Digvijaya Singh said.