Subspecies: erythrogaster
The long tail indicates an adult bird. If so I believe it is a male. But if it is an adult, why is it so pale then on the throat and the front of the head?
Subspecies: erythrogaster
Adults and a juvenile: The juvenile number two from the left, lower row. The diffuse breast band with circle shaped lower edge. The very short tail is the result of both the angle to the camera and of the fact that juvenile birds still don't have the elongated outer tail feathers of the adult. However, you easily perceive the white ovals on the outer rectrices which are unique for example in comparison with Bank Swallows. In this case the bird has already acquired some orange colored body feathers which excludes any doubt.