Horrified people in Paraná, Brazil, ran for their lives when squiggly black dots rained down from the sky.

Footage of this bizarre spectacle shows thousands of creepy-crawly arachnids infesting an enormous web as an amazed and terrified crowd of onlookers watch a scene straight out of a science fiction movie.

The creatures have since been identified as belonging to the genus species of Anelosimus eximius. What sets these spiders apart from their eight-legged cousins is their habit of spinning huge ‘sheet webs’ and living en masse rather than the solitary existence of most arachnids.

These social spiders live in large colonies and create webs that measure up to twenty-five feet wide. Roughly fifty thousand individual spiders can make up one colony, coexisting as they hunt, build webs, clean and maintain their giant structures, and share the food caught in their webs.

Another strange trait of the Anelosimus eximius is that mother spiders feed their own babies, along with other young spiders in the colony, by regurgitating food for them in a birdlike manner.

The video has been seen by nearly two million people on YouTube since it was posted, and most of them thanked their lucky stars that they didn’t have to witness the event in person.

“Thanks for a glimpse into my own personal hell, Satan,” said one person after they watched it. Another viewer commented, “There’s no way I would even be able to stay there and film that.”