A teacher at a secondary school has been suspended for repeatedly slapping the face of a student, reportedly because he refused to call her “mum”, after video of the incident was widely seen online.

The video shows a teacher grabbing a schoolboy’s wristand leading him through a passage. She then stops to speak to the boy and points to his face before slapping it. The impact takes off his face mask.

The teacher is then seen shouting at the boy and hitting his face again. The impact of the second slap was so hard that his face jerked to one side.

Thatchapol Polrat, deputy dean of Ramkhamhaeng University overseeing its demonstration secondary schools, said on Thursday that the guardian of the student met with him last week.

Mr Thatchapol said he had forwarded a report of the incident to the disciplinary office of the university for further action. Pending its ruling, the teacher concerned has been suspended.

Meanwhile, school officials have discussed compensation with the student and his guardian, Mr Thatchapol said.

The deputy dean said the boy told him he was “okay”, and the boy’s classmates have also given him moral support.

The video was posted online by a woman who said she was the schoolboy’s aunt.

She said the teacher had become angry after the boy rejected her instruction to call her “mum”, telling her he had only one mother.