Investigators from the Santa Rosa Police Department served warrants in Concord and Vacaville as part of their ongoing investigation into illegal weapons sales. The investigation focused on "Invisiglock" switch devices that can convert Glock-style pistols into fully automatic firearms, which are illegal under California law. 19-year-old man was detained during the operation and several additional conversion devices were found hidden inside a first-aid container. The police also seized two fully automatic weapons.