A catfish posing as Marco Rubio using an AI voice disguiser contacted senior government officials on the messaging app Signal.
The imposter, who has not been identified by the authorities, sent voice and text messages using artificial intelligence technology (AI) to mimic the US secretary of state’s voice and speech patterns, The Washington Post reported.
They contacted a member of Congress, a US governor and three foreign ministers, seemingly with the goal of “gaining access to information or accounts,” authorities said.
Mr Rubio is the second member of Donald Trump’s administration to be impersonated using AI, after a catfish pretending to be Susie Wiles, the chief of staff, contacted Republican lawmakers earlier this year.
In June, Mr Rubio’s impersonator created a Signal account with the name “Marco.Rubio@state.gov” to contact foreign diplomats and politicians, according to a State Department cable.
“The actor left voicemails on Signal for at least two targeted individuals and in one instance, sent a text message inviting the individual to communicate on Signal,” it reads.
It is likely to renew concerns about the use of the app by senior members of Mr Trump’s administration after national security figures accidentally leaked US military plans to a journalist in March.
The State Department said it would “carry out a thorough investigation and continue to implement safeguards to prevent this from happening in the future”.
FBI investigation into Wiles AI catfish
The FBI opened an investigation in May when a catfish using AI to pose as Ms Wiles, the US president’s chief of staff, texted and called her contacts asking for cash.
Ms Wiles privately told colleagues that her phone had been hacked by and mined for contacts.
One Republican lawmaker said they had been asked to compile a list of people to be pardoned by Mr Trump, while another was asked for a cash transfer.
Hany Farid, a professor specialising in digital forensics at the University of California Berkeley, said the catfish attempts did not need to be particularly sophisticated to succeed when coupled with AI software.
“This is precisely why you shouldn’t use Signal or other insecure channels for official government business,” he told The Washington Post.
In March, Pete Hegseth, the US defence secretary, accidentally leaked US military plans to bomb Houthi rebels in Yemen to the journalist Jeffrey Goldberg when he was accidentally added to a Signal chat by Mike Waltz, then the US national security adviser.
Mr Waltz was sacked by Mr Trump in May, then nominated as US ambassador to the UN. His confirmation hearings will reportedly take place next week.