Djinn have also been described as forms of shadow beings, ghosts, demons, inter-dimensional beings.The most popular explanation seems to be that they are some sort of other-dimensional beings whose dimension of origin occasionally overlaps with ours, which is said to explain their ethereal appearance and fleeting nature. As with most entities there is no logical or scientifically valid explanation. These beings are in violation of generally accepted scientific principles.
Simon Parkes is a multiple contactee with Reptilian and Mantid type aliens djinn. He goes into great detail about these beings in a unique and informative presentation.