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.

Image: Pic: US Secret Service

Image: Pic: US Secret Service

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