The post-mortem report confirmed the girl was raped and then strangled by unidentified persons, they said.
On Tuesday night, the girl was sleeping along with her family under the porch when she went missing following which her family members kept looking for her the whole night, they said.
Mahendra, a farmer, found her body in his farm yesterday morning.
Officiating Circle officer Ajay Kumar Gautam reached the site with a police team and on the complaint of the girl's father, a murder case was registered against unidentified persons.