A network of sophisticated electronic devices at various sites around New York that could be used to disable the city’s mobile phone system has been dismantled by the Secret Service, officials say.
They said the network was also used to anonymously make assassination threats against senior US officials and for criminal activities, Sky’s US partner NBC News reported.
The development came hours before President Trump addressed world leaders gathered at the United Nations General Assembly in New York this week.
Matt McCool, the head of the agency’s New York Field Office, said officials were looking into whether those behind the network planned to use it to disrupt the assembly.
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The system was used for “communication between foreign governments and individuals that are known to federal law enforcement here in the US”, according to officials.
Secret Service agents have seized more than 300 co-located SIM servers and 100,000 SIM cards in five locations within 35 miles of New York as part of an ongoing investigation, said officials.
The devices could be used to carry out telecommunications attacks including disabling mobile phone towers, enabling cybersecurity attacks and allowing encrypted communication between criminal groups and threat actors.
The officials said 80g of cocaine, illegal firearms, computers and mobile phones were also found.
Mr McCool said: “These devices allowed anonymous, encrypted communications between potential threat actors and criminal enterprises, enabling criminal organisations to operate undetected.
“This network had the potential to disable cell phone towers and essentially shut down the cellular network in New York City.”
‘Equivalent of 100,000 mobile phones’ worth of data’
He added: “These recovered devices no longer pose a threat to the New York tristate area.
“We will continue working towards identifying those responsible and their intent, including whether their plan was to disrupt the UN General Assembly and communications of government and emergency personnel during the official visit of world leaders in and around New York City.”
He said forensic analysts were examining the equivalent of 100,000 mobile phones’ worth of data.
The tri-state area where the network was located includes New York, Connecticut and New Jersey.
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Officials said agents were looking through the SIM cards to establish who came up with the network.
“We’re working through every call, every text, every search made on those SIM cards,” according to an official.
Mr McCool said the network was discovered by the Secret Service after the number of threats to US officials they were protecting got bigger earlier this year.
“Following multiple telecommunications-related imminent threats directed towards senior US government officials this spring, the US Secret Service began a protective intelligence investigation to determine the extent and impact these threats could have on protective operations,” he said.
The Secret Service declined to name the officials who were threatened.
No arrests have been announced.