The student's family said he had done nothing wrong. (Representational)

The parents and relatives of a Class 12 student allegedly thrashed his teacher in Surat today, a day after he slapped him in class, the school authorities said.

The school officials said the teacher has been admitted to a hospital.

While no case has been registered so far, the student's parents and the school management have both filed complaints, the police said.

Both the incidents-the teacher slapping the student and his being beaten up by the family---were captured on the CCTV cameras installed in the school.

In the footage from Tuesday, the teacher can be seen slapping the student in front of others in the school lobby.

Another video shows a group of around 15 people assaulting the same teacher in the school compound. While some of them punched and kicked him, one person even used a stick to beat the teacher.

Mahesh Ramani, the chairman of the school said that the teacher has been admitted to a hospital after the attack.

"On Tuesday, some students started shouting in the toilet during the recess. When the teacher called the student in question and sought an explanation, he confronted him. The teacher slapped the student for his behavior and he grabbed his collar. Angered by the boy's act, he slapped him about 10 times," Mr Ramani said.

He added that the teacher was suspended as soon as the school principal learned about the incident from the student's parents, who came to the school on Wednesday morning.

"Although we suspended the teacher, the student's family caught hold of the teacher and mercilessly thrashed him in the school premises. They even used abusive language," Mr Ramani added

However, the boy's father claimed that his son was not at fault.

"My son did not do anything. Even today, it was the school management which incited us," he said.