With Team Anna campaigning against his party in Hisar bypoll, Congress leader Digvijay Singh on Tuesday questioned Anna Hazare on why he was not attacking the BJP and cautioned him against "lofty promises" by that party of making him a presidential candidate.

"You have never raised your voice against the BJP," Singh, who has been a vocal critic of Team Anna, said and asked why he was "silent" on the issue of corruption when the BJP-led NDA was in power.

"What is being seen now is that you have been strongly opposing the Congress and as against this you have been praising BJP's Narendra Modi despite the fact that there is no Lokayukta in Gujarat for the past nine years," Singh said in the four-page open letter written just two days before the Hisar bypoll.

Referring again to his claim that BJP has offered to make Hazare the presidential candidate, he said, "The talk is that the BJP wants to make you a candidate in the Presidential election next year. You become a candidate, but beware of the lofty promises of the BJP, which is in the habit of leading people up the garden path."

Singh, a former Madhya Pradesh chief minister, asked Hazare as to whether he was oblivious as to with whom he and his associates will be aligning by the call to vote against the Congress.

"Are you not aware of the history of the family of late Bhajan Lal? Are you not acquainted with the history of Chautala family? Are you oblivious of the fact that there were cases of corruption pending against them in courts?," he asked.

Singh told Hazare that an impression was gaining ground that he has been surrounded by people who have always been opposed to the ideology of the Congress.

"Be it Shanti Bhushan or his son Prashant or your colleague Arvind Kejriwal. All these people have been opposed to the Congress. These people are taking benefit of your clean character for their own political gains," he said attacking Team Anna members.

Singh told Hazare that he has been taking several decisions under the influence of these associates "which are divergent with his values of life".

While referring to the show of support by RSS including its chief Mohan Bhagwat, Singh alleged that Hazare's statements that he is not aware that Sangh has extended support to their movement raises questions about his "credibility".

In an obvious reference to L.K. Advani's Jan Chetna Yatra, Digvijay Singh said BJP leaders have now been making strong statements on the issue of black money, but they had done precious little when they were in power. "That time too, you remained silent."

Recalling that whenever he had taken the name of RSS in connection with his campaign, "You have said that I should be sent to a mental hospital, but I don't want to say anything on the matter as I respect you."

He claimed that now even Bhagwat has admitted to Sangh's support and said so clearly in his Dussehra address in Nagpur.

Prior to this, Govindacharya has also said the same thing and Sangh has even written a communication to its volunteers in your support, Singh said.

"Are you not aware that Sangh spokesman Ram Madhav had come to your dais and had extended you support. During the conclusion of your programme at the Ramlila grounds, special mention was made of the RSS and BJP chief Nitin Gadkari while extending thanks," he said.

"In such a backdrop, your statements that you are not aware that the Sangh has extended support to you raises questions on your credibility," Singh said.

"My simple question to you is that while conducting such a huge nation-wide campaign, are you not aware which organisations are supporting you and do you still want to go ahead by taking their support."

At the same time, he hailed Hazare for his life-long social service and told the Gandhian that "political workers like me have taken inspiration from you".

"You are welcome if you want to enter politics. But, you select your associates and support us in such a way that it would not lead to shattering the faith of the people," he said.

Singh, however, wondered whether actions of Team Anna would lessen corruption and would it tantamount to support to clean politics.

The Congress general secretary said that Team Anna's opposition to Congress on the ground that it was against the Lokpal Bill was itself based on "wrong perception" and wanted Hazare to ponder over as to whom they will benefit.