A 13-year-old girl was allegedly set on fire by a boy when she resisted his attempt to sexually assault her, a police official said today.

The girl was admitted to the district hospital and her condition was reported to be serious, he said.

She was alone at her house in Sustani village on Saturday as her family members had gone for work at an agricultural field.

Taking advantage of the situation, the boy forcibly entered her house and allegedly tried to sexually assault her, Khujner police station in-charge Indraraj Singh said.

However, when the girl resisted his move, the boy poured kerosene over her and set her on fire, he said.

Taking a serious note of the incident, Rajgarh district Superintendent of Police Simala Prasad directed the security personnel to launch a search for the boy, who was traced and taken into custody last night, Singh said.

The girl, who belonged to a scheduled caste, suffered nearly 50 per cent burn injuries and her condition was serious, police said.

A case under relevant sections of the Indian Penal Code and the Protection of Children from Sexual Offences (POCSO) Act was registered against the accused, the police said, adding that an investigation was on into the incident.