Local news reports said the corpse with a "mysterious skull" was found by two residents next to the River Kovashi, on Sunday, in the Russian town of Sosnovy Bor, a town built in 1958 to serve the Leningrad Nuclear Power Plant.
It is said that the locals, who spotted it by chance, initially believed it could be a mutant chicken embroyo that had been discarded.
However, local experts have been so far unable to say what it is.
One researcher was quoted as saying: "It seems that this body is neither fish nor fowl - this creature has a mysterious skull, no neck and wings."
The body was also looked at by experts from the Institute of Biophysics in Krasnoyarsk, who said it was impossible to make a quick identification.
It seems that this body is neither fish nor fowl - this creature has a mysterious skull, no neck and wings.
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Biologist Yegor Zadereev said: "Extensive studies are needed to determine what kind of creature or organism it is."
It is thought it will be sent to Moscow for further tests.
But Alien investigators are already convinced it is of extra terrestrial origins.
Scott C waring, who edits UFO Sightings Daily, said: "This tiny alien body was found near a river in Russia and has no resemblance to any animal known.
"Russian scientists are confused over what it could be and said they need to wait for the results of the tests, which are probably DNA I assume."
It is thought it will be sent to Moscow for further tests.
But Alien investigators are already convinced it is of extra terrestrial origins.
Scott C waring, who edits UFO Sightings Daily, said: "This tiny alien body was found near a river in Russia and has no resemblance to any animal known.
"Russian scientists are confused over what it could be and said they need to wait for the results of the tests, which are probably DNA I assume."
By Jon Austin, EXPRESS