"This statement is highly objectionable. The RSS is a nationalist organisation," BJP spokesperson Syed Shahnawaz Hussain told reporters here.
"The Congress is doing politics over dead bodies. Is Digvijay Singh above the home ministry and all Indian agencies that he can say anything? Some people in Indian politics have a verbal diarrhoea, they don't think before speaking," he added.
"(Congress president) Sonia Gandhi should give a clarification on this," he said.
Singh, in reply to a question on possible involvement of right-wing organisations in the recent serial blasts in Mumbai, said he had evidence of the involvement of the 'Sangh' in terror activities.
"Nothing can be ruled out as far as probe in the blasts is concerned," he added.
He, however, clarified that he did not have any evidence on the RSS's involvement in the serial blasts of Wednesday in Mumbai.
"If they want evidence about Sangh's (RSS) involvement in terror activities, I have evidence but not in this case," Singh said.The RSS is a right-wing Hindu organisation established in 1925.