A girl, who was sexually harassed by three boys a couple of days ago, set herself afire in her house at Kavalkaranpatti on Wednesday.

The 13-year-old Class VIII student resorted to the extreme step when her parents were away. With severe burn injuries, she is being treated at the Mahatma Gandhi Government Hospital in Tiruchi.

The police arrested the two – aged 18 and 15 years – on the charge of sexually harassing the girl and are on the look out for the third boy.

Police sources said the girl who went to the market lost money while returning home on Monday evening. She went in search of the money when the boys allegedly gagged the girl, took her to a nearby brick chamber and harassed her. She complained about the offence to her parents the same night. On a complaint from the girl, the Kulithalai All Women Police registered a case against the three boys under Sections 7 and 8 of the Protection of Children from Sexual Offences Act and under the IPC sections, including 323 (voluntarily causing hurt). A declaration was obtained from the victim at the Tiruchi hospital by a judicial magistrate on Wednesday, the sources said.