YouTube alien hunter Streetcap1 posted the footage showing a cloud of light appearing and disappearing above Colima Volcano in Mexico.
The user believes it is hiding an alien spaceship.
The video was uploaded with the description: “It disappears then reappears way above the summit. It looked strange. When you think about it, it is the perfect cover.”
And the clip has sparked a fierce debate about the existence of aliens.
One commenter, who claimed to be from the area, said the volcano is something of a UFO hotspot.
Caden Cuevas said: “It was very often to see lava run down specially at night and one could see objects flying around during both the day time and night.
“My mom said that when she was younger she once saw this ‘metalic humanoid’ walking towards the crater of the volcano.”
Kevin Masters was sold, saying: “Absolutely fantastic video. Best proof I have seen for ages.”
This is not the first time "alien activity" has been captured on camera at the volcano.
Back in October, Streetcap1 videoed a weird flying object appearing to take off from the mouth of the huge crater.
And the last time it erupted back in January, a UFO was filmed shooting out of the lava as it spilled ash.
GONE: The bright light disappears – sparking debate about whether it was caused by aliens