This story is what nightmares are made of.

On Tuesday, an Arizona homeowners stumbled across what he thought was were three rattlesnakes in his Mesa garage. A snake removal company was called to safely remove the venomous creatures. But what Rattlesnake Solutions snake wrangler Marissa Maki found was quite shocking.

In the man’s garage were actually 20 snakes. Of the snake den, five adult western diamondback rattlers and 15 babies were found. Reportedly, one of the adult snakes was pregnant.

Most of the rattlers were found curled around the base of a hot water heater.

The western diamondbacks are distinctive with triangular-shaped heads. They are found throughout the southwestern United States and Mexico. And though their venom is far less toxic than other rattlesnake species, this type of snake is responsible for the majority of snakebite fatalities in northern Mexico and the greatest number of snakebites in the U.S.

The snake wrangler took on the task of removing the multiple snakes from the garage with the use of tongs to pick each snake up and placing them into large plastic buckets. The snakes were then relocated to in a nearby desert area.

After the removal was completed, Rattlesnake Solutions reported they believe there could have been even more snakes in the garage at one point. Several shedded skins were discovered in the garage, which suggests as many as 40 snakes could have lived in the space over a period of time.