A massive illegal electronic device network capable of crippling cell towers and jamming 911 calls across New York City was uncovered by the Secret Service — just as world leaders prepared to descend on Manhattan for the UN General Assembly, officials said Tuesday.

Investigators discovered the trove of devices — including more than 300 co-located SIM servers and 100,000 SIM cards – at multiple locations within 35 miles of the United Nations.

“The potential for disruption to our country’s telecommunications posed by this network of devices cannot be overstated,” Secret Service Director Sean Curran said.

A wall of SIM boxes seized by the U.S. Secret Service.
This photo provided by the US Secret Service, in New York, Monday, Sept. 22, 2025, shows a wall of SIM boxes at the location where they were seized by the agency.AP
Officials warned the devices had the capability of carrying out a wide-range of telecommunications attacks — including spamming networks with up to 30 million text messages a minute — that could have had “catastrophic” consequences for the city.

“It can take down cell towers, so then no longer can people communicate, right? …. You can’t text message, you can’t use your cell phone. And if you coupled that with some sort of other event associated with UNGA, you know, use your imagination there, it could be catastrophic to the city,” Matt McCool, the special agent in charge of the Secret Service’s New York field office, said.

“Given the timing, location and proximity and potential for significant disruptions to the New York telecoms system, we moved quickly to disrupt this network.”

SIM card packaging seized by the U.S. Secret Service.
This photo provided by the US Secret Service, in New York, Monday, Sept. 22, 2025, shows some of the 100,000 SIM cards that were seized by the agency.AP
It wasn’t immediately clear exactly when the cache of hidden devices was seized.

The hidden network was found as part of a sweeping Secret Service probe that kicked off in the spring following telecommunications-related threats targeting senior US government officials, according to investigators.

When agents ultimately raided the locations, they uncovered rows of servers and shelves stacked with SIM cards – including more than 100,000 that had already been activated, as well as a large number still waiting to be deployed, McCool said.

U.S. Secret Service Special Agent in Charge Matt McCool speaks during an interview in his office.
Matt McCool is the special agent in charge of the Secret Service’s New York field office.AP

McCool warned of the havoc the network could have caused if it had been left intact — comparing the potential impact to cellular blackouts that followed the 9/11 terror attacks when networks crippled under the strain.

Officials said they haven’t uncovered a direct plot to disrupt the UN General Assembly but noted there was no ongoing threat to the Big Apple.

Investigators are still probing who is responsible but believe perps from certain countries used the system to send encrypted messages to organized crime groups, cartels and terrorist organizations.

Forensic analysis is still in its early stages, McCool said.

“We need to do forensics on 100,000 cell phones, essentially all the phone calls, all the text messages, anything to do with communications, see where those numbers end up,” he said.