Four people reportedly raped the 14-year-old girl at the Marvelene's Inn, the guest house run by Mr Lyngdoh's son Nathaniel Osbert Rymmai.
"The job of a Home Minister is to protect women and children, but in Meghalaya it is a reverse. It is sad and shocking that in Meghalaya, where women are held in high esteem, such an incident has taken place," she said, addressing an election rally in Dalu near the India-Bangladesh border.
Ms Irani was campaigning for Bharatiya Janata Party (BJP) candidate Kurosh R. Marak, who is contesting from Dalu constituency in West Garo Hills district. Marak is also a sitting member of Garo Hills Autonomous District Council.
"Meghalaya has a unique culture and tradition and the confidence of women and children is fascinating. Our party believes in empowering women and we will be able to drive the agenda in Meghalaya to further their cause."
Wooing the 9,29,314 women electorate to vote in favour of the BJP, Ms Irani promised that if her party was voted to power, a dedicated women police force would be in place to ensure security of women.
"The pride of women has to be restored and we will ensure that women in Meghalaya feel safe, secure and independent," she said.
"Women in India work tirelessly cooking food on traditional 'chula' to bring smile on their children's face. So, Modi decided to provide gas cylinder to poor women to ease their problem," Ms Irani said.
Accusing the Congress-led state government of failing in its responsibilities for 50 years, which "Modi made possible in three years", she said: "In absence of proper healthcare facilities, our people have to avail treatment in neighbouring Bangladesh.
The BJP, which failed to win a single seat in the 2013 assembly elections, has fielded its candidates in 47 out of 60 seats. Among the party's contestants are four former legislators of the ruling Congress-led Meghalaya Alliance.
Elections in the state are due on February 27 and the counting March 3.
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