Police in Cameroon have arrested a teacher after a video emerged online allegedly showing him brutally beating a nine-year-old boy.

The incident is suspected to have taken place at a primary school in Doula, Cameroon's economic capital.

The video has been widely shared on social networks causing a wave of indignation.

It shows a totally naked boy being held by his arms and feet by four other children, while a man hits him with a rubber hose and then a machete.

According to an eyewitness, the pupil was punished for failing to give a reason for his absence from school for a few days.

A police investigation is underway.

Corporal punishment is outlawed in Cameroon, but some schools still use it.