MILWAUKEE (CBS 58) -- A 20-year-old Milwaukee man is in custody after the North Central High Intensity Drug Trafficking Area team and Milwaukee Police Tactical Enforcement Unit executed a search warrant Tuesday, Sept. 12. 

Officials say three firearms were found -- two equipped with conversion devices (switch) which converted them into fully automatic firearms. 

Additional gun parts, magazines, ammo, an unattached full auto switch and 110 grams of marijuana were also located in the residence. 

Police say switch devices are very dangerous and illegal in the state and federally.

In a press release, the Milwaukee Police Department said, "The device by itself, regardless if it is installed on a slide or not, is considered by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) to be a machine gun, making possession of the device illegal in the United States."

Anyone who knows or has seen anyone use a switch is asked to contact Milwaukee police at 414-935-7360, or to remain anonymous, call Crime Stoppers at 414-224-TIPS.