Pierluigi Paganini
September 23, 2025
The U.S. Secret Service uncovered a covert communications network near the U.N. in New York, seizing 100,000 SIM cards and 300 servers. The operation, capable of sending 30 million texts per minute, could disable cellular towers and conduct surveillance on a massive scale, raising new concerns over mobile network security.
“The U.S. Secret Service dismantled a network of electronic devices located throughout the New York tristate area that were used to conduct multiple telecommunications-related threats directed towards senior U.S. government officials, which represented an imminent threat to the agency’s protective operations.” reads the advisory published by the US Secret Service.
“This protective intelligence investigation led to the discovery of more than 300 co-located SIM servers and 100,000 SIM cards across multiple sites.”
The agents also discovered illegal firearms, computers, cell phones, and 80 grams of cocaine alongside the communications equipment, a reminder of the blurred lines between cyber operations and traditional criminal organizations.
According to investigators, the clandestine communications network wasn’t tied to the U.N. Assembly, but authorities warned of the potential impact due to the proximity to the U.N. headquarters in New York.
Intelligence experts speculate the network could also be linked to the operations of nation-state actors.
“According to investigators, the cache was not directly linked to the U.N. General Assembly underway at the time, but its proximity and potential raised serious concerns.” reported the NYT. “One official noted that authorities had never before encountered an illicit communications network of this magnitude, prompting some experts to suspect the involvement of a nation-state.”
The dismantled cache was a full parallel network composed of racks of servers with 100,000+ SIMs able to flood carriers, disrupt services, or launch mass phishing campaigns. Beyond outages, experts warn it could enable espionage, eavesdropping, or tracking officials.
A preliminary analysis of the SIM card showed links to a foreign nation and criminal groups, including cartels, highlighting overlaps between nation-state actors and cybercrime rings.
“While forensic examination of these devices is ongoing, early analysis indicates cellular communications between nation-state threat actors and individuals that are known to federal law enforcement.” continues the Secret Service.
“This looks sophisticated and expensive — my instinct is espionage,” Anthony J. Ferrante, former White House cybersecurity official and now global head of cybersecurity at FTI Consulting told NYT.
Researchers believe that only “a handful of countries such as Russia, China, or Israel” would have the resources and capabilities to set up such a covert communications network.
While the scale of this discovery is unprecedented, it is not the first time that communications networks have been exploited or hijacked.
In 2017, security experts in Washington, D.C., detected multiple IMSI catchers (devices that mimic legitimate cell towers to intercept calls and texts) near sensitive sites, including the White House and Capitol Hill. In 2021, Mexican authorities dismantled parallel telecom networks operated by drug cartels. These included custom towers and relay systems used to coordinate trafficking operations beyond the reach of legitimate carriers.
The incident shows that communications networks can be weaponized. Threats like disabling cell networks, spying, or hijacking data are real and impact security and safety. Finding such a network near the U.N. highlights the risks during high-profile events like the General Assembly, where millions of messages per minute and anonymous communication could be exploited for espionage.
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