Arjun, a Class IX student, did not return from his school yesterday following which his family lodged a missing complaint, a police official said.
"His cycle was found at the bus stand and search operations are on," the official said.
He is believed to be from the family of one of the two youths who were killed in Kawal village in 2013. Their murder had led to communal violence in Muzaffarnagar and adjoining areas in which mode than 60 people were killed and thousands displaced.