Currently, any device that is modified with a switch is considered a machine gun under federal law.
PENNSYLVANIA (WPVI) -- Police across Pennsylvania are issuing a warning on Wednesday on an attachment for guns that can convert an ordinary weapon into a fully automatic pistol.
The tiny and inexpensive "switch" lets criminals create machine guns, increasing danger on the streets and to law enforcement.
Action News spoke with Montgomery County District Attorney Kevin Steele, who described so-called gun "switches" as simple but lethal.
"They are too easy to get. We need this banned and we need it soon," he says.
Montgomery County Detective Eric Nelson, a firearms and ballistics expert, showed Action News what a switch is and how they are used.
"We are seeing it in all different types of guns. Rifles, pistols, and various calibers. So pretty much any gun," Nelson explained.
The rapidly increasing popularity of switches is not confined to the suburbs, experts say.
Captain James Kearney, the commanding officer of the Philadelphia Police Gun Investigation Group, says just one recent example involved the shooting near a SEPTA bus stop that ended with eight teenagers injured this past March.
"These guys got out of a car -- one of whom had a switch on their 40 caliber -- and unloaded 23 rounds about less than two seconds," said Kearney.
Currently, any device that is modified with a switch is considered a machine gun under federal law and is therefore illegal on a federal level.
Steele explained why a state law making switches illegal is critical.
"Law enforcement needs a tool to fight back against this, and without a ban, we're relying solely on the federal authorities and most cases get prosecuted on a local level," he said.
Currently, switches are illegal in several states across the country, including Delaware.
A bill to outlaw switches in Pennsylvania has already passed the House but has yet to be considered in the State Senate.
The Pennsylvania District Attorneys Association has already communicated with lawmakers in Harrisburg that the organization is united in the call to make that bill a law as quickly as possible.
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