A 24-year-old Brazilian man obsessed with UFOs has vanished, leaving behind a room with encrypted messages written all over the walls.

Bruno Borges disappeared on March 27 and hasn't been seen since.

Borges was working on a series of encrypted books believed to be about extra-terrestrial life.

When police searched his room, they found walls covered with coded messages including quotes from the Bible and Leonardo da Vinci.

Across the floor were symbols associated with the Illuminati and a life-size statue of philosopher Giordano Bruno.

The 16 th century Italian friar was one of the first philosophers to propose that distant planets fostered life.

He was burned at the stake during the Roman Inquisition on charges of heresy.

Most curiously, Borges' bedroom had no furniture in it.

All the changes to Borges' room were made last month while his parents were away on a long trip.

"We've tried to call him on his cell phone, but it's off," Borges' father told Globo.

"He's never gone before, he did not take anything and the last time we saw him he was leaving home."

However his family do not believe he has met with foul-play.

"We were very worried. Now we think he's okay. He has a project, which is the publication of these 14 books. I think he had to do it that way," his sister Gabriella said.

Bruno Borges beside a poster of E.T. (Facebook)

Bruno Borges. (Facebook)