Neighbours of the boy, Pulli, called police after he was seen shouting for food from a window of the house in Kashiram Colony area here.
His mother, who had married again after the death of Pulli's father, had left for Delhi with her second husband after locking the boy inside, police said.
The police today broke open the door and freed Pulli.
According to neighbours, the house was locked for last five days and the child's mother, Nasreen, went to Delhi with her husband.
The police has handed over the custody of the child to his step-grandmother. PTI Corr ASY
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