Shadow People

I managed to find a brief reference to 'shadow people' whilst undertaking some research. It seems reports have been made over many years but little is known or even surmised about them.
One theory, rather unhelpfully, suggested shadow people were a kind of anti-matter ghost equivalent. Possible I guess but leaving me no wiser than before.
I noted that the accounts in the research I came across seemed to suggest dark shadow like people but in a seemingly 'static' type appearance. In other words, lacking the movement shown by many ghosts (and people).
The accounts I have on file, though admittedly few, were all of dark shadow like people, moving like a person though ephemeral like a 'typical' ghost.
Those involved were extremely frightened and believed the entities were evil and present to steal their souls.
So I'll continue my research into this 'stranger than strange' phenomena.
And if you have anything to add please email me at encounters@writeme.com