President Donald Trump announced he directed Jeff Sessions to look into banning bump stocks and similar devices.
"Moments ago, I signed a memorandum directing the attorney general to propose regulations to ban all devices that turn legal weapons into machine guns," Trump said.
In October, the Las Vegas shooter used a bump stock to increase the fire rate of his weapons.
It's illegal for private citizens to own fully automatic guns made after 1986.
A bump stock effectively turns a semi-automatic — or single-fire weapon — into a rapid-fire weapon by making the gun "bump" against the shooter's shoulder and trigger finger.
Trump said he's meeting with governors next week to discuss ways to keep students safe following the school shooting in Parkland, Florida.