One of the new images, the box of slides and the sign for UFO mecca Roswell in New Mexico
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.
Many are clutching onto the hope that they are the genuine article, while several others claim they have been hit by a sophisticated hoax, thanks to modern technology.
The ‘Roswell Slides’ appear in Chicago
This second image supposedly shows a closer view with an unreadable label next to the body
This photograph of an alleged 1940s autopsy on an alien body released in 1995 was a hoax
I think it’s physical evidence. I think we have physical evidence. A picture is worth a thousand words.
They claim the photographs are a bid to cash in on the 20th anniversary of a previous scam, when amazing pictures claiming to reveal a secret autopsy on an alien corpse emerged in the 1990s.
The UFO Chronicles website spoke with Tom Carey and Don Schmitt, authors of Witness to Roswell, an account of the Roswell incident.
Mr Carey said: “It was three-and-a-half to four feet-tall. The head is almost insect-like. The head has been severed, and there’s been a partial autopsy; the innards have been removed, and we believe the cadaver has been embalmed, at least at the time this picture was taken.
“I think it’s physical evidence. I think we have physical evidence. A picture is worth a thousand words.”
While Mr Schmitt argued: “No, it’s not physical evidence, and it’s important to understand when a picture has value.
“Usually, a photo can begin to be considered supporting evidence only when time, location and the photographer are known.
“In addition, it’s vital to know what instrument recorded the data. We don’t have the camera or any of the other information about how the slides of the body were taken.
“The other claims are all based on speculation, trying to make the slides and the Ray’s history fit into the narrative of the Roswell story.”