It is a tradition in some parts of India to train pigeons for recreation. A whole flock lives on the roof-top of the house of the master. The birds are free to fly around and they always come back after sojourns around the neighbourhood. The birds are usually marked with some pigment for easy identification. These two broke away from the flock to race each other before joining the group again of ten again!
Though more common in the older parts of Delhi, it is quite an unusual sight to see trained birds in the more modern parts of this bustling city.