NEW DELHI: India's longest-serving female prisoner, who was convicted over the assassination of former Prime Minister Rajiv Gandhi, walked out of prison Thursday on a 30-day parole to arrange her daughter's marriage.

Nalini Sriharan was granted parole earlier this month by the Madras High Court after spending nearly three decades in jail over her role in Gandhi's murder by a female suicide bomber in 1991.

Sriharan, an Indian national, was arrested soon after the bombing and found guilty -- together with her husband and 25 others -- of conspiracy and helping the teenage bomber Thenmozhi Rajaratnam.

Her death sentence was commuted on a clemency plea by Gandhi's widow in 2000. Three others are still awaiting execution.

Sriharan was pregnant when she was arrested, and gave birth to the child in prison. Her daughter is a UK national and a doctor.

She was released from Vellore Central Prison and will spend time at her home in the town, but has been barred by the court from speaking to the media or politicians.

She had previously been granted short paroles to attend her father's cremation and memorial.

Gandhi -- prime minister between 1984 and 1989 -- was campaigning for mid-term national elections in 1991 when militants targeted him over his decision to send the Indian army to Sri Lanka.

Sri Lanka was in the grip of a decades-long armed conflict between the majority Sinhalese government and minority Tamils demanding an independent country for the ethnic group.

The civil war which ended in 2009 killed at least 100,000 people, and the Tamil rebels enjoyed widespread support from their ethnic kin in Tamil Nadu.

Rajiv Gandhi was the son of former PM Indira Gandhi -- assassinated in Delhi by her Sikh bodyguards in 1984 -- and the father of Rahul Gandhi, who ran for prime minister in the recently held general elections. —AFP