Over the years, there have been countless sightings of UFOs diving into Mexico's Popocatepetl volcano, especially while it's erupting. Here's a video of the most recent sighting, on May 31.
I think we all know what this means. There is a massive alien civilization beneath the Earth, and that's why the NSA has to monitor all the phone conversations in the United States. To protect us in case one of these UFOs grabs us and tries to hurl us into an erupting volcano!