Government school teachers protested at a school in Nangloi, west Delhi after two Class 12th students stabbed a teacher to death on Monday. Both students have been arrested, the police said. 

Teachers held a protest on Tuesday demanding better security as students who failed or have low attendance have been threatening teachers.

An argument had broken out between the teacher, Mukesh Kumar, and the two students in a classroom where other students were writing an exam. One of the students, who had been expelled for low attendance, barged in to the classroom and started arguing with the teacher. His friend, who was writing an exam, joined his friend in the altercation. Both of them then hit the teacher and stabbed him. 

They fled the seen after stabbing Kumar thrice. They left the teacher bleeding on the floor. The incident took place around 5 pm on Monday. The teacher died in the hospital. 

One of the accused is two months short of 18 while another is 18 years of age. The police have said that the students "lost their temper."

"I was submitting exam sheets ...suddenly I heard some noise and saw two children running. When I went there I saw Mukeshji was bleeding ...we immediately took him to hospital," said another teacher who was on the premises during the incident. He added that the two students had been threatening Kumar and the principal of the school since they had failed multiple times. 

"He told us that there are six children who failed thrice and their parents were threatening him," said Kumar's brother-in-law.