San José police say they shut down a sprawling illegal gun operation after arresting a 20-year-old man accused of cranking out and selling conversion devices that turn standard pistols into fully automatic weapons. Investigators say search warrants turned up guns, ammunition, and materials used to make those parts, which they believe were headed for buyers around the Bay Area and into the Central Valley.
In a press release posted by San José Police Media Relations, the department identified the suspect as Kenneth Tafoya of Lockeford. Officers arrested him today in Stockton and booked him into the Santa Clara County Main Jail. According to the release, detectives opened the case on November 15 after getting a tip from the Santa Clara County Adult Probation Office, with the California Highway Patrol and the Bureau of Alcohol, Tobacco, Firearms, and Explosives brought in to assist.
SJPD Arrests Suspect for Manufacturing, Sales, and Distribution of Illegal Firearmshttps://t.co/WWPzBijBtC
— San José Police Media Relations (@SJPD_PIO) January 27, 2026
"The importation, manufacturing and sale of illegal firearms will not be tolerated," Chief Paul Joseph said in the statement. Santa Clara County District Attorney Jeff Rosen also weighed in, praising the multi-agency teamwork that, in his view, means fewer illegal guns and less violence on local streets.
Devices that convert semiautomatic pistols into fully automatic weapons, commonly called "Glock switches," have drawn mounting state and federal scrutiny as police recover more of them each year. Rising seizures and new legislation aimed at blocking the sale of firearms that can be easily converted have been documented by outlets such as The Los Angeles Times and advocacy groups like Everytown for Gun Safety.
What police say they recovered
San José detectives say searches of homes tied to the investigation turned up one shotgun, one rifle, one pistol, one machine gun conversion device, multiple rounds of live ammunition, firearm manufacturing precursor materials, multiple magazines and multiple spent casings. Investigators allege that Tafoya imported or manufactured at least 1,700 of the conversion devices that can turn a pistol into a fully automatic weapon.
The department listed the investigation under case number 25-310-9702 and included contact information for Detective Epperson for anyone with tips, according to the release from San José Police Media Relations.
Legal context and penalties
Under federal law, these conversion parts are treated as machine gun components. That means unregistered possession, manufacture, or transfer can bring serious federal charges and prison time, according to reporting by AP News.
Large seizures have triggered high-profile prosecutions in other parts of the country. In one case publicized by The Department of Justice, the U.S. Attorney's Office in the Western District of Washington secured federal charges in a case involving more than 100 Glock switches. That prosecution was held up as an example of how aggressively federal authorities are moving on these devices.
San José police say their case is still active. Prosecutors will decide on specific charges after reviewing the evidence, and detectives are asking anyone with additional information to contact the assigned investigator using the direct number included in the department's release.
