CNN  — 

The Trump administration rolled out a new federal regulationTuesday officially banning bump-fire stocks.

Those who possess the devices, which make it easier to fire rounds from a semi-automatic weapon by harnessing the gun’s recoil to “bump” the trigger faster, will have 90 days to turn in or otherwise destroy them from the date that the final rule is published in the federal register – likely this Friday – according to senior DOJ officials.

Bump stocks gained national attention last year after a gunman in Las Vegas rigged his weapons with the devices to fire on concertgoers, killing 58 people.

Officials at the Bureau of Alcohol, Tobacco, Firearms and Explosives had previously concluded bump stocks were merely a gun accessory or firearm part, not subject to federal regulation, but President Donald Trump called on the Justice Department to outlaw the devices soon after the tragedy.

Justice Department officials told CNN Tuesday they took a “fresh look” at the case law, technology, and the devices and their functionality “in light of modern developments.”

The rule concludes that bump-fire stocks, “slide-fire” devices, and devices with certain similar characteristics all fall within the prohibition on machine guns by allowing a “shooter of a semiautomatic firearm to initiate a continuous firing cycle with a single pull of the trigger,” and therefore, they are illegal under federal law.

Acting Attorney General Matthew Whitaker signed the new rule Tuesday morning, according to the officials – a notable move given the string of legal challenges surrounding the constitutionality of his appointment. The officials said they stood ready to defend against any challenges to the rule, and pointed to the fact that the Office of Legal Counsel at the Department signed off on it.

As for how many gun owners will be affected by the new rule, officials explained it was difficult to provide precise figures, saying bump stocks “aren’t widespread, but they are not uncommon.”

Trump said in October he told the National Rifle Association that “bump stocks are gone,” but how the group responds to the final rule remains to be seen. A spokesperson for the NRA said in October 2017 that the ATF “should review bump-fire stocks to ensure they comply with federal law,” but made clear it opposed the broader gun-control legislation raised by some in Congress.