This is the terrifying moment a four-year-old boy runs for his life as a building wall collapses just behind him.

CCTV footage shows the child, wearing a green shirt, walking along the pavement in the San Francisco neighbourhood of Bucaramanga, Colombia.

Without warning, the wall behind him gives way, sending a cloud of dust, bricks, and cables crashing to the ground just steps away. The boy is seen fleeing the scene as debris falls.

Reports said the child had just finished lunch inside a restaurant with his grandmother and was leaving the building as his mum arrived to collect him on August 16.

Witnesses said they heard a loud crash and initially believed a vehicle had struck the restaurant.

The boy's grandparent told local media she feared her grandson had been buried in the rubble when she lost sight of him, but later found he was already safe outside with his mother.

Authorities believe recent heavy rainfall may have weakened the structure, leading to the sudden collapse.