Hyder (19) had been pestering the 13-year-old girl belonging to the same community to accept his proposal, but the girl had turned down it.
The girl's parents had also warned the youth and also informed his parents.
When the girl was on her way to a private tailoring institute, Hyder accosted her, stabbed her several times and chopped off her ear lobe, resulting in her death on the spot, police said.
He then banged his head on a boulder to end his life, but passers-by rushed him to a hospital.
Police have registered a case.