The two pictures were made public at a special conference in the US yesterday.
They are suggested to show the remains of an alien found dead by US authorities at a ranch near Roswell, New Mexico, in 1947,
It is alleged the grainy pictures were found in a collection of 40 colour slides in the attic of a well-connected American couple when their property in Midland, Texas, was being cleared before sale.
A slick movie-style documentary trailer accompanied the release of the pictures, suggesting to be the story of an investigation by a journalist after they came into his possession.
The clip described how the pictures were among the personal snaps of well-travelled couple Hilda Blair Ray, a prominent local attorney, and her husband Bernard, a geologist working in the oil industry at the time.
The pictures appear to show a humanoid with a large head on a clear glass shelf and in a glass enclosure.
They have been described as of extremely poor quality compared to the rest of the slides in the collection, said to be taken between the mid 1940 and 1950s.
The release of the images has sparked huge debate and division among UFO and alien groups online.
As they should. An altogether unconvincing dog and pony show, IMO. To read more and view the video, click here.