The girl went missing on February 24 while returning to Satalkhedi village from tuition in Ramgangmandi town. Her body was noticed by a villager who informed the police, Sukait SHO Ravish Samariya said.
The girl's parents had a missing report following her disappearance, he said.
Primary investigation revealed that the girl was apparently depressed over her failed love affair and allegedly committed suicide by jumping into the river, the SHO said, adding that the name of a boy was found written in her books.
Based on the report, a case under Indian Penal Code (IPC) sections 363 (kidnapping), 366 (abducting or inducing woman to compel her marriage) was lodged, Samariya said.
The body has been handed over to the family after post-mortem, he said.