Schoolchildren ran for cover as a dust devil tornado tore through the field.

The kids were about to go to their classes when the weather phenomenon formed in the middle of the open area of a school in Zamboanga City, the Philippines, on March 23.

Footage shows the youngsters screaming and fleeing from the 20ft-high twister. Some of them were stunned and watched while the others ran inside the building for safety.

One of the pupils, Macy Andrea Bazan, said: ‘My friends and I were scared because it was the first time we have seen one and it happened inside the school.'

Dust devil tornadoes are types of whirlwinds that form when the sun heats a patch of land and the air above becomes warmer and rises quickly.

Cooler air then moves into the low-pressure gap left by the rising warm air. The new drafts of cooler air also heat up and rise and the cycle continues, picking up dust and debris and making the spiral visible.

They are not as dangerous as supercell tornadoes, which can cause severe damage.