John McAfee's widow has said her husband was not suicidal when she last spoke to him - hours before he was found dead in a Spanish prison.
The antivirus software tycoon died in a Barcelona jail this week while awaiting extradition to the US, and authorities indicated that the 75-year-old killed himself.
But his wife, Janice McAfee, said: "His last words to me were, 'I love you and I will call you in the evening'.
"Those words are not words of somebody who is suicidal."
Mrs McAfee was speaking outside Brians 2 prison in Barcelona, where she was collecting her husband's belongings.
McAfee, who founded anti-virus software McAfee in the 1990s, was arrested at Barcelona airport in October last year on a warrant issued in Tennessee for allegedly evading over $4m (£2.87m) in taxes.
Just hours before he was found dead, Spain's national court agreed to his extradition to America.
"We were prepared for that decision and had a plan of action already in place to appeal that decision," Mrs McAfee, 38, said.
"I blame the US authorities for this tragedy. Because of these politically motivated charges against him my husband is now dead."
Mrs McAfee was the tycoon's third wife - he met her in 2012 and they married a year later.
Spanish officials said they were conducting a post-mortem examination on his body but the results could take "days or weeks".
A judicial investigation is also being held into his death.
McAfee's lawyer, Javier Villalba, said his client's death had come as a surprise to his wife and other relatives, adding he would seek to get "to the bottom" of his death.
"This has been like pouring cold water on the family and on his defence team," Mr Villalba said.
"Nobody expected it, he had not said goodbye."
Although Mr Villalba said he had no evidence of foul play, he blamed the death on "the cruelty of the system" for keeping a 75-year-old behind bars for economic and not blood-related crimes after judges refused him bail.
"We had managed to nullify seven of the 10 counts he was accused of and even so he was still that dangerous person who could be fleeing Spain if he was released?" said the lawyer.
"He was a world eminence, where could he hide?"
Prosecutors in Tennessee had accused Mr McAfee of failing to report income from promoting cryptocurrencies while he did consulting work, made money from speaking engagements, and sold the rights to his life story for a documentary.
The criminal charges carried a prison sentence of up to 30 years.
The entrepreneur was born in Gloucestershire in the UK and led an eccentric life after selling his stake in his highly successful antivirus software company.
He twice made long-shot runs for the US presidency and often professed his love for drugs and guns in public remarks.
In 2012, the prime minister of Belize urged McAfee to hand himself into the authorities in relation to the death of his neighbour.
McAfee went on the run after Gregory Faull, 52, was shot on the Caribbean island where they both lived.
Belize police said McAfee was a "person of interest" while prime minister Dean Barrow expressed doubts about the businessman's mental state.
Mr Barrow said: "I don't want to be unkind to the gentleman, but I believe he is extremely paranoid, even bonkers."
McAfee was reportedly later found legally "liable" via a default judgment for the death of Mr Faull.
:: Anyone feeling emotionally distressed or suicidal can call Samaritans for help on 116 123 or email email@example.com in the UK. In the US, call the Samaritans branch in your area or 1 (800) 273-TALK.