Chinese state-affiliated hackers intercepted audio from the phone calls of US political figures, including an unnamed campaign adviser of Donald Trump, the Washington Post reported on Sunday.
Various media outlets reported on Friday that the Trump campaign was made aware last week that the Republican presidential candidate and his running mate, JD Vance, were among a number of people inside and outside of government whose phone numbers were targeted through the infiltration of Verizon phone systems.
The FBI and the US Cybersecurity and Infrastructure Security Agency confirmed they were investigating unauthorized access to commercial telecommunications infrastructure by people associated with China, though they did not name the Trump campaign in the statement.
Reuters later reported that Chinese hackers also targeted phones used by people affiliated with the campaign of Kamala Harris.
The Post now reports that the hackers were able to access audio from a phone call from a Trump campaign adviser, as well as unencrypted communications such as text messages of the individual.
Trump’s campaign and the FBI did not immediately respond to a request for comment.
The Trump campaign was hacked earlier this year. The US justice department charged three members of Iran’s Revolutionary Guard Corps with the hack, accusing them of trying to disrupt the 5 November election.
Verizon said on Friday it was aware of a sophisticated attempt to target US telecoms and gather intelligence and was working with law enforcement.
Congress is also investigating and earlier this month US lawmakers asked AT&T, Verizon and Lumen Technologies to answer questions about reports Chinese hackers accessed the networks of US broadband providers.
The Chinese embassy in Washington DC said last week it was unaware of the specific situation but said China opposes and combats cyber-attacks and cyber thefts in all forms.