Well, this news isn't exactly reliable. I mean, just reading the statement of the anthropologist, you realize that this is biased (unless it was simply poorly translated):
"...At first we believed it to be a child's body until Spanish and Russian doctors came and confirmed that, yes, it's an extraterrestrial being"
They didn't confirm anything, they just expressed their opinion (and a few people already pointed out how the translation might be wrong, and that they might have meant to say "weird" instead of "alien").
And this without wanting to discuss how unlikely it would be that alien lifeform would resemble Earth life so much, or how many other possibilities like "native" animals (deformed humans or monkeys)are extremely more plausible than that of an alien. I am curious about the results of any test performed on the bones, though, as it doesn't look human, but I can't identify what animal it is... The photo doesn't even show the size of the skull, or if the skeleton is complete and how big it is. What I have seen in other pictures show the ribs a bit better, and they don't seem to have the proportions of a human being, at least.