An unknown force killed life on Mars 

An international team of scientists came to the conclusion
that Mars was previously inhabited, but an unknown force
destroyed all living organisms on it, according to SpaceCom.
Researchers analyzed soil samples from Gale Crater and
concluded that Mars was inhabited in ancient times. Five years
ago, the Curiosity rover mined clay minerals very similar in
properties to glauconite clays. These complex hydrous
aluminosilicates are common on Earth and form exclusively
in stable ecosystems. The results of this study allowed planetary
scientists to make the assumption that for millions of years Mars
was suitable for the existence of biological life, that is, living
organisms lived here.
Some scientists are inclined to believe that life originated on
Mars, and migrated to Earth millions of years ago. They believe
that millions of years ago, the Red Planet underwent a monstrous,
mysterious anomalous catastrophe. After that, large fragments of
Mars broke off, flying into space. Some of them reached Earth. 
One of these meteorites was discovered in Antarctica. It was then
that scientists concluded that these fragments never got hot enough
to destroy the microorganisms inside. In 2020, Japanese scientists
were able to establish the age of bacteria found in a Martian 
meteorite. Alien bacteria were 4 billion years old. Researchers 
believe that it was then that the meteorite brought an extraterrestrial
life form to our planet. Perhaps that we are all Martians.