- HSI ran the three-week sweep, dubbed Operation Signal Break, from June 22 to July 10
- The targets were SIM box systems, which pack thousands of SIM cards to route scam calls and phishing texts
- Agents deployed across six states, with more than 11 HSI field offices taking part
Federal agents have spent three weeks breaking up SIM box networks operating inside the United States, Immigration and Customs Enforcement said Friday. Homeland Security Investigations ran the sweep, called Operation Signal Break, from June 22 to July 10.
ICE described the seized systems as command-and-control infrastructure for large-scale telecommunications fraud. The targets were transnational criminal organizations using the equipment against American victims.
How Do SIM Farms Enable Phone and Text Fraud?
A single SIM box can hold hundreds or thousands of SIM cards and route calls and messages over the internet, hiding where the traffic actually originates. Operators use that cover to push out thousands of scam calls and phishing texts.
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Where Did Operation Signal Break Focus?
The DHS Cyber Crimes Center led the effort with support from HSI Los Angeles. Teams of special agents, criminal analysts, and computer forensics analysts were deployed to California, Florida, Texas, Massachusetts, New York and New Jersey. ICE said more than 11 HSI field offices took part.
What Has HSI Seized in Its SIM Box Investigations?
ICE released cumulative figures dating to 2024 rather than results specific to Signal Break. Over that stretch, the agency counted more than 116 federal criminal search warrants and 68 disrupted SIM farms in 15 states.
Seizures over the same period total more than 500,000 SIM cards, over 1,900 SIM boxes, and upward of $700,000 in illicit proceeds. The cases have resulted in a criminal arrest and 11 administrative arrests.
What Happens to the Data HSI Seized?
Analysts at HSI Los Angeles will analyze seized SIM data and network artifacts in collaboration with the Counter Threat Finance Unit and the Cross Border Financial Crimes Center. ICE set three aims for that review: identifying victims, quantifying fraud losses, and tracing the proceeds to Chinese transnational criminal organizations and their distribution networks.
Indictments, asset seizures and sanctions could follow.
