Brazilian authorities are seeking to bring charges against Glenn Greenwald, the journalist who published Edward Snowden's intelligence agency leaks.
Mr Greenwald has been accused of "helping guiding and encouraging" a criminal group that hacked into the phones of Brazilian officials.
The journalist had recently published stories describing private messages between public prosecutors.
At this point, federal public prosecutors have proposed the charges.
However, a judge still needs to decide whether to formally indict him.
Six other individuals have also been accused of illegal telephone interceptions and conspiracy among other related crimes.
Brazilian prosecutors allege that, during his interactions with the group, Mr Greenwald advised its members to delete messages that they had passed on to him.
Mr Greenwald has not yet publicly responded to this particular allegation.
Last year, Mr Greenwald and colleagues published a series of ten investigative reports on news site The Intercept, which detailed "a massive trove of previously undisclosed materials" allegedly by Brazilian prosecutors and other officials.
They quoted from messages that had been sent via Telegram, a privacy-focused app that claims to be able to keep "messages safe from hacker attacks".
The Folha newspaper said that those whose accounts had allegedly been breached included justice minister Sergio Moro and prosecutor Deltan Dallagnol, who is coordinating Operation Car Wash - a probe into the country's biggest ever corruption scandal.
'I'll keep working'
After details of the accusations against him were published, Mr Greenwald issued a statement via The Daily beast news site. In it, he noted that Brazil's Supreme Court had ruled last year that the administration should drop its investigation into him because it violated his press freedom rights.
"Less than two months ago, the federal police, examining all the same evidence cited by the public ministry, stated explicitly that not only have I never committed any crime but that I exercised extreme caution as a journalist never even to get close to any participation," he added.
"We will not be intimidated by these tyrannical attempts to silence journalists.
"I am working right now on new reporting and will continue to do so."
The New York-based Freedom of the Press Foundation has described the Brazilian attorney general office's actions as being "beyond disturbing" and an "outrageous violation of press freedom".
Edward Snowden, who was granted asylum by Russia after he fled the United States in 2013, tweeted his reaction to the news.
"Absolute red alert: This is unbelievably naked retaliation for revealing extreme corruption at the highest levels of [Brazilian President] Bolsonaro's administration and an existential threat to investigative journalism in Brazil," he wrote.
Last year, President Bolsonaro commented in public that he thought Mr Greenwald could face legal repercussions in Brazil over his reporting activities.
Following news of the allegations levelled at Mr Greenwald, Eduardo Bolsonaro - the president's son and an MP - tweeted: "Glenn Greenwald always said he loved Brazil and wanted to get to know the country in-depth. Maybe he will get to know [one of Brazil's] jails…"