Nalini has shared an account of the 2008 meeting with Priyanka Vadra at a jail in Vellore in the book "Rajiv Murder: Hidden Truths and Priyanka - Nalini Meeting", released on Thursday in Chennai by MDMK chief Vaiko.
Priyanka Vadra, says Nalini, "looked straight at me for nearly two minutes" in silence.
"When I raised my eyes to look at her, her cheeks had turned red."
Nalini, 51, and her husband Murugan are among seven convicts serving a life sentence in the 1991 killing of Rajiv Gandhi by a suicide bomber of the Lankan Tamil separatist outfit LTTE, who greeted the Congress leader with a sandalwood garland and a bomb strapped to her chest during a rally.
Priyanka's lips quivered, claims Nalini, as she asked "Why did you do it? My father is a good man, a soft man, you could have resolved anything over a discussion with him."
And then she broke down.
She says she replied: "Madam, I don't know anything. I won't even hurt an ant. I'm a prisoner of circumstances. I've never thought of hurting anyone even in my dreams."
In the 85-minute meeting, Priyanka Vadra, now 44, was "largely patient and a keen listener", Nalini says, "but turned angry and even made me feel scared whenever she talked about the other convicts."
In two chapters on the meeting, Nalini claims she discussed the case and told her that she, her husband and other convicts were forced to sign confessional statements.
Nalini's death sentence was commuted to a life term in 2000 following the intervention of Rajiv Gandhi's wife and Congress president Sonia Gandhi, the mother of Rahul and Priyanka Gandhi. Her daughter Megara lives in the UK.
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