Federal Prosecutors in Michigan announced 11 people from Benton Harbor and Grand Rapids have been charged with drug and gun-related crimes.

The announcement was made on Thursday, Dec. 15.

U.S. Attorney for the Western District of Michigan Mark Totten said the so-called ‘firearm switches’ enable a semi-automatic firearm to fire as any as a thousand bullets per minute.

“Over the past few years we have seen a significant rose in violence related to firearms across America and here in Michigan as well, The emergence of switches is especially concerning.. They pose an emerging threat to our communities, to our children, to our law enforcement officers, and to anyone who stands in the path of their indiscriminate spray,” Totten said.

U.S. attorneys say the investigation centered on trade in devices used to convert semi-automatic guns into machine guns.