The police said the accused, identified as Sohail, went to the girl's residence and poured kerosene on her and set her on fire.
The girl was immediately shifted to the Osmania Hospital for treatment where the doctors said she has received 70% burn injuries. The accused has also received burn injuries.
According to police, Sohail, who knew the victim for past one year, was upset that girl's parents, after finding about his relationship with her, have decided to marry the teenager to some other person.
Further investigation is underway. (ANI)