Antivirus software entrepreneur John McAfee has been indicted on fraud and money laundering conspiracy charges alleging that he and cohorts made more than $US13 million ($16.9 million) by fooling investors zealous over the emerging cryptocurrency market.

Mr McAfee, 75, was charged in a newly unsealed indictment in Manhattan federal court along with Jimmy Gale Watson Jr, who served as an executive adviser on what prosecutors described as Mr McAfee's "so-called cryptocurrency team."

Prosecutors said Mr Watson, 40, was arrested in Texas and would make an initial appearance on Friday, local time, before a federal magistrate judge in Dallas.

Mr McAfee, authorities said, is detained in Spain on separate criminal charges filed by the US Justice Department's tax division.

It is not clear who will represent the men.

"McAfee and Watson exploited a widely used social media platform and enthusiasm among investors in the emerging cryptocurrency market to make millions through lies and deception," US Attorney Audrey Strauss said in a statement describing crimes in 2017 and 2018.

In October, Mr McAfee was charged in federal court with evading taxes after failing to report income made from promoting cryptocurrencies while he did consulting work, from speaking engagements and from selling the rights to his life story for a documentary.

Mr McAfee developed early internet security software and has been sought by authorities in the US and Belize in the past.

The indictment said Mr McAfee failed to file tax returns from 2014 to 2018, despite receiving "considerable income" from several sources.

In July 2019, Mr McAfee was released from detention in the Dominican Republic after he and five others were suspected of traveling on a yacht carrying high-calibre weapons, ammunition and military-style gear, officials in the Caribbean nation said at the time.

AP