Singh, a former Army chief, said a curtain should not be put on the scandal by targeting only Tyagi. The ongoing probe, he said, will bring out facts in the case.
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"It is a long process. Only one man cannot be there. If the qualitative requirement is changed, somebody is involved in it or is it only Tyagi. It's a big line. Let's not try to put a curtain and say only SP Tyagi is involved. There are many more people," Singh said.
Asked about credibility of allegations against Congress president Sonia Gandhi and some other party leaders in the alleged scam, Singh said "There is enquiry that has to be done. Let that enquiry be completed. We will know the facts."
The Minister said Congress leaders who are allegedly involved in the scam should do some "introspection" and that it will be good for the country if they came forward with the "truth". The Congress has called the charges against its leaders "false and baseless".
Asked about Rahul Gandhi's comment that he was happy to be targeted in the wake of BJP's attempts to drag him into CWG and the VVIP chopper scam, Singh said the Congress vice president was playing the "victim" card.
"A lot of people want to play victim. If he wants to play that he is most welcome," he said.
BJP MP Kirit Somaiya had recently sent a letter to ED and CBI requesting them to check Gandhi's links with a real estate developer allegedly involved in the CWG scam and also the alleged connections of his political aide with a middleman in the AgustaWestland deal.
Somaiya had said that Guido Haschke, an alleged middleman in the chopper deal is common in both the scams and that he is linked to Christian Michel, an accused in the VVIP chopper scam.
"Kirit Somaiya is one of those who do a lot of research and I am quite sure there must be some fact in that (the allegations)," Singh said.