Talking to reporters, she said, "I am surprised as to how Modi, being a politician, being a human being, and being from Gujarat, can speak about the riots and that phase of violence without showing any pain."
She, however, added that she was not passing a judgment on Modi as she did not know him well.
Gandhi-Bhattacharya, 78, is vice-chairman of the Gandhi Smriti and Darshan Samiti.
Modi was recently named the Bharatiya Janata Party's prime ministerial candidate for the forthcoming Lok Sabha polls.
"Once I watched Modi speaking in Gujarat from a distance. I can't judge him. But when he mentions the excesses of the Gujarat riots, I do not see any anguish on his face," she said.
Talking about the conditions at refugees' camps in Gujarat which were set up after the riots, she said, "I was so pained (upon seeing them) that I could not sleep for the next six months."
About Modi's infamous "puppy coming under the wheels of a car" remark, she said it was a case of use of "indecent language".
Asked whether Modi becoming the prime minister would pose a danger to the democratic values of India, Gandhi- Bhattacharya said, "I won't name anyone, because by singling out one person, others cannot be condoned. Whoever comes to power must have compassion and courage."
Image: Children, orphaned by post-Godhra riots, play at an orphanage in Anjar, Gujarat ' Photograph: Reuters
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