The victim had suffered 90% burns and was referred to Delhi hospital, after a brief treatment at Civil Hospital in Lucknow.
Her condition deteriorated after 8:30 pm, following which doctors increased medicine dosage. However, she had cardiac arrest and died later at night, a spokesperson for Safdarjung Hospital said.
Earlier in the day, the victim’s brother said that his sister wanted to live and her attackers should be hanged.
On December 5, the 23-year-old was attacked by five men when she was on her way to meet lawyers in Rae Bareli.
She was allegedly raped a few months ago and had filed a complaint in March this year, the police said.
The woman and one of the prime accused in the case had reportedly married last year, against the wishes of their families.