"The girl was a student of Class XII at Kendriya School. She had returned from her coaching class around 7 pm yesterday and gone to her room," said the in-charge of the Manduadih police station here.
"Around 9 pm, she was found hanging in her room by her father. She was rushed to hospital, but declared 'brought dead'," he added.
A suicide note, addressed to her mother, has been found from the girl's room, which mentions the name and phone number of the boy she had an affair with.
According to the police, her family was opposed to the alliance and this could be the reason for her suicide.