Chicago Mail Facility Intercepts 269 Illegal Gun Switches from China in April
Customs officers seized 269 illegal gun modification devices from China at Chicago mail facilities in April, intercepting conversion switches that transform legal handguns into fully automatic weapons bound for American communities.
Federal officers pulled 269 illegal gun modification devices from mail packages flowing through Chicago facilities last month, stopping contraband that turns legal handguns into fully automatic weapons before it reached American streets.
U.S. Customs and Border Protection agents intercepted the devices across 107 shipments in April. The haul included 255 pistol automatic fire conversion switches and 14 suppressors, all manufactured in China and destined for addresses across the country.
The seizure underscores the ongoing threat of foreign-made illegal firearm components entering through U.S. mail systems. It also reflects the enforcement priorities of the Trump administration's border security agenda under Homeland Security Secretary Markwayne Mullin.
"These illicit attempts to import weapon modification devices pose a danger to our communities," Michael Pfeiffer, Chicago Field Office Acting Director of Field Operations, said. "CBP's dedication and attention to detail when scrutinizing cargo protects our nation."
The devices, commonly called "Glock switches," convert standard semi-automatic handguns into weapons capable of firing up to 1,200 rounds per minute. Federal law classifies them as machine guns even when separated from any firearm. Possession carries up to 10 years in federal prison and a $250,000 fine.
Chicago agents seized 1,507 weapon-modifying devices in 2024 alone. Federal authorities have identified the city as facing one of the worst switch problems in the country. The Bureau of Alcohol, Tobacco, Firearms and Explosives has recovered more than 31,000 such devices nationwide between 2019 and 2024.
Recoveries surged 570 percent from 2017 to 2021 compared to the 2012–2016 period. The steady climb illustrates how smuggling operations scaled their efforts over time.
Smugglers went to lengths to conceal the shipments. Many packages lacked proper declarations or ATF importation approvals. Some suppressors were disguised as water pipes, while switches arrived labeled as "small books" or "stickers."
One seized switch bore a sticker reading "F*** THE ATF." The message revealed smugglers' full awareness of their devices' illegal status.
The Chicago operation fits into a broader national enforcement effort. Operation Silent Night launched in 2019 after CBP noticed a massive influx of illegal silencers from China. The initiative has since seized 42,888 illegally imported silencers, 4,868 firearms, and resulted in 204 arrests.
The Department of Justice also seized more than 350 website domains in September 2024 that sold Glock switches and silencers from China. The online crackdown targeted the digital infrastructure enabling these smuggling networks.
CBP tied the April seizures directly to the administration's border security mandate in a statement. "Fulfilling President Donald J. Trump's mandate, the Department of Homeland Security and U.S. Customs and Border Protection, under the leadership of DHS Secretary Markwayne Mullin, have delivered the most secure border in history, stopping dangerous criminal aliens, weapons, and illicit narcotics from entering our communities, which will keep America safe for generations to come," the agency stated.
Mullin received Senate confirmation on March 23, 2026, and oversees the agency's border enforcement operations. The CBP statement explicitly credits the administration's border security priorities for enabling such interceptions.
"Our frontline CBP officers continue to exercise vigilance in all mail environments; and their inspectional experience coupled with an exercise of keen observational techniques resulted in these seizures," Pfeiffer said.
Chief CBP Officer Nadia Varela noted the increasing volume of such contraband. "Over the last fiscal year, we've seen an uptick in the interception of Glock switches, auto series, silencers, all types of contraband coming from China and Hong Kong," Varela said in a February 2025 interview. "So, CBP has chosen to focus on intercepting a lot of these parcels, get them off the streets on the back end."
Gun suppressors present a separate legal landscape. They remain legal in 42 states but illegal in eight, including Illinois, New York, California, and New Jersey. The April seizure included 14 suppressors bound for various U.S. locations, highlighting how smugglers circumvent state-level firearm regulations.
The threat is adapting as Chinese supply faces mounting pressure. ATF officials report a shift toward 3D-printed switches that cost as little as 40 cents to produce. CBP continues to interdict manufactured devices at the border, keeping them off American streets.
"In the last five years, ATF has recovered more than 31,000 machine gun conversion devices," Christopher Bombardiere, ATF LA Field Division Special Agent in Charge, said. "These devices are not gun accessories. They are illegal and considered machine guns under federal law."
The April 2026 Chicago seizure stands as one of the largest single-month interceptions to date. The 269 devices exceeded the monthly average from 2024, when agents seized 1,507 devices across the entire year. Border agents continue serving as a critical barrier against illegal weapon modifications that threaten communities nationwide.