Earlier this month, a man shot five people in Northern California.
Kevin Janson Neal could not acquire guns legally, so he built the rifles himself-- the same ones that resulted in the tragedy.
These homemade weapons are commonly known as "ghost guns": They are unregulated, untraceable, and potentially undetectable, making them even more dangerous when they fall into the wrong hands.
Take Two sat down with Mark Tallman, executive director of the security consultant company Creative Assurance, to talk about these phantom weapons.
"The fundamental definition of a DIY gun is that it can be made and assembled outside of the mainstream manufacturing line," Tallman explained. "It's really difficult to estimate how big the market is because there is no record."
It is legal under federal law to acquire the components necessary to put together these firearms, including the lower receiver, the part that makes gun a gun. "There are many forms of these 'ghost guns,' some crude, some more sophisticated," said Tallman.
Not everyone who puts together homemade guns are involved in criminal activities. In fact, the vast majority are believed to be gun hobbyists who enjoy the customization process. However, recent high profile cases highlight the possibility for abuse.
"To me as a security researcher, this is not just a gun policy issue," said Tallman. "It's a harbinger for other security issues to come with the Fourth Industrial Revolution. It's just easier and easier to make stuff."