The doctors performed various laboratory tests on the remains, which have been disputed by academics, scientists, and archaeologists who say they are part of a hoax.

Among the critics is Professor Brian Cox, a physicist and presenter, who said they are “way too humanoid” to be real.

The remains were shown in glass cases at an official event at Mexico’s Congress last week, where UFO enthusiasts were excited to see them.

The politicians who attended the event were told that the specimens were found in Cusco, Peru, and that they were about 1,000 years old.

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The event was led by Jaime Maussan, a journalist and UFO researcher, who swore under oath that almost a third of their DNA is “unknown” and that the specimens do not fit in “our terrestrial evolution”, according to Mexican media.

“These specimens are not part of our evolutionary history on Earth,” he said in his presentation to Mexican government officials and representatives from the US.

“They are not beings recovered from a UFO crash.”

“Instead, they were found in diatom (algae) mines and subsequently became fossilized,” he cited.

Professor Cox has requested that a sample be forwarded to the biotechnology firm 23andMe for an independent confirmation that the specimens are of terrestrial origin.

He said last week, “It’s very unlikely that an intelligent species that evolved on another planet would look like us.”

This is not the first time that Mr. Maussan has claimed to have found an extra-terrestrial being.

In 2015, he said that a mummified body found near Nazca in Peru was an alien, but it turned out to be a human child.

Scholars, archaeologists, and scientists have collectively stated that the mummified remains, which UFO researchers assert are extraterrestrial, are typically altered human bodies.

They have also said that some of the smaller ones, like those shown in Mexico last week, are bodies made of animal and human bones.

The examinations conducted by Mexican medical professionals on Monday indicate that these remains originated from a singular skeleton rather than being composed of various distinct bones.

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Mr Maussan said last week that the specimens had been studied before at the Autonomous National University of Mexico.

He stated, “Scientists utilized radiocarbon dating to obtain DNA evidence, and X-rays revealed that one of them contained ‘eggs’ inside.”

Mexican politicians said last week that the information had left them with “thoughts” and “concerns” and that they wanted to “continue talking about this”.