Hours after the bill was signed, Birmingham Mayor Randall Woodfin issued a direct warning to what he called the “switch boys” that they will face prosecution.

The law, which goes into effect immediately, targets devices that turn semiautomatic handguns into makeshift machine guns.

Alabama has banned gun conversion devices that have the ability to convert semi-automatic pistols into fully automatic weapons. The conversion devices, sometimes referred to as Glock switches, are already banned under federal law,