The nation’s top law enforcement officer committed Thursday to prosecuting individuals that create undetectable 3D printed firearms on Thursday.

“Under federal law, it is illegal to manufacture or possess plastic firearms that are undetectable. Violation of this law is punishable by up to five years in prison,” Attorney General Jeff Sessions said in a statement. “We will not stand for the evasion, especially the flouting, of current law and will take action to ensure that individuals who violate the law by making plastic firearms and rendering them undetectable, will be prosecuted to the fullest extent.”

Mr. Sessions did not elaborate on any plan of strategy to track or monitor the creation of such weapons.

The Justice Department filed a brief on Wednesday stating that the lawsuit filed by Washington State Attorney General Bob Ferguson should be dismissed. The DOJ argued that it only has jurisdiction over exports posing a security threat from foreign actors, so they cannot regulate domestic concerns.

Supporters of Defense Distributed, the original site that published plans for 3D printed guns, argue that the debate over the software lies in free speech, not gun legislation. They argue information its self is protected, and separate from actually creating the guns.

In defiance of a judge’s order against Defense Distributed, the plans were published by a website called Code Is Free Speech and spread through social media.