Incredible footage has shown several 'UFOs' spotted in a mysterious ancient canyon where experts claim they have found 'evidence' of portals.

The eerie phenomenon was shown during Tuesday's episode of the History Channel's Beyond Skinwalker Ranch.

Hosts Paul Beban, veteran journalist, and Andy Bustamante, an ex- CIA agent,  traveled to Rock Art Ranch, a private cattle ranch in northern Arizona, to investigate the thousands of ancient Native American petroglyphs.

The men spoke with former Navajo Ranger Jon Dover about the ancient rock carvings that show animals, three-fingered creatures seemingly representing extra terrestrials, and what is believed to be portals. 

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