The girl, considered a dalit or 'untouchables,' according to India's traditional caste system, was noticed by a 22-year-old man walking with her mother along a path in the town of Mathura reserved for upper caste Indians.
The attacker, Madan Singh, ordered her to stay away from the area, but she ignored him. "When he tried to stop her, she got scared. He then set her on fire," throwing her into a pile of burning waste by the side of the road, the girl's father told the national NDTV TV channel.
The child suffered 50% burns over her body and is in critical condition. The man admitted the crime and has been charged with attempted murder.
"It is wrong...It is a general road and everybody was moving on it...There were so many women and children going through that road. The road was never obstructed by people and it was an act of an individual," a police spokesman said.
Violence against dalits has been on the rise in recent weeks in north India, especially in Uttar Pradesh according to the CNN-IBN channel, despite the state being governed by a dalit woman, Mayawati, the leader of the Bahujan Samaj Party.
Although India's constitution prohibits caste-based discrimination, the idea that all people are divided into four main groups, is still prevalent. The 'untouchables' are considered impure and forced to work in the most menial of jobs.