Blueprints for the world's first 3D printed gun have been downloaded more than 100,000 times in just two days.
Even more worryingly, the CAD files are hosted on Kim Dotcom's encrypted site Mega - meaning those uploading the files are essentially untraceable.
The weapon consists of 15 printable parts - undetectable to metal detectors - and a nail, which is used as the firing pin.
The gun fires a standard .38 round
Cody Wilson, founder of Defense Distributed (DD), made the blueprints freely available on the company's website after successfully test-firing it last week.
Speaking to Forbes, he said: “I recognize that this tool might be used to harm people.
"That’s what it is — it’s a gun. But I don’t think that’s a reason to not put it out there. I think that liberty in the end is a better interest.
"This is about enabling individuals to create their own sovereign space."
The idea that anyone can simply download blueprints for a working gun and then print it in their own homes has sparked a heated debate about gun control.
An American senator has already called for legislation to ban the weapons.