Sarpang police have detained a student, 17, of Sarpang Lower Secondary School for allegedly punching a teacher.
On May 31, the teacher had asked two students to leave the classroom after they were found chewing betel nut.
After the class was over, the student had apparently charged the teacher for making him leave the classroom. Following a brawl, the student allegedly punched the teacher.
The school had involved the police since the nature of offence fall under criminal case.
The case is being investigated.