"I have full sympathy for Amar Singh and I believe that he will be proved innocent," Digvijay Singh told reporters at Raghogarh.
He also strongly condemned Wednesday's blast outside the Delhi High Court and asked people not to politicise the issue of terrorism.
Terror activities should be curbed with an iron hand and fundamentalists of any community should not be spared, he said.
When asked about Anna Hazare, he said he respects the Gandhian a lot, and would like to congratulate the social activist for two things. He forced the RSS people to wear white caps instead of (the usual) black ones, and hold the national tricolour in hand, in place of RSS's saffron flag.
Singh denied that he had ever described Hazare as the mask of the RSS.