A little boy was almost run over when he fell off the back of a toy cart being pulled by his grandmother as they rushed over a pedestrian crossing - and she did not notice he had been left behind.

Fortunately, an alert stranger spotted the potential disaster and ran over to the crossing, grabbing the child from the road and bringing him to safety just as the old woman realised that he was missing from the back of the cart.

CCTV cameras captured the incident that reportedly took place in Hezhou, in Guangxi region, southern China, on December 2.

In the video, the little boy is seen sitting on the cart being pulled by the elderly woman, who appears to be his grandmother, as the two approach a pedestrian crossing.

Seemingly in a rush to get off the street, the grandma hurried along but accidentally dropped the toddler in the middle of the road.

But she apparently did not notice him fall off and kept rushing to the pavement while vehicles honked at her to get out of the way.

Fortunately, a man who was walking nearby spotted the imminent danger and ran to help the child before a car could accidentally run him over.