The Spanish newspaper reported that several unnamed sources close to the case said that the medical examination ruled McAfee took his own life before he was found dead in jail on Wednesday.
McAfee has been held at the Spanish prison near Barcelona since he was detained last October at Barcelona airport following years on the run from US authorities.
The news of McAfee’s death came on the same day that news broke that his extradition to the US had been approved, where he was set to face charges of tax evasion.
In the immediate aftermath the Catalan justice department confirmed in a statement that the likely cause of death was a suicide, Reuters reported.
McAfee’s family, namely his wife, has said that she did not believe her husband was suicidal and has called for a “thorough investigation” of his death.
“His last words to me were ‘I love you and I will call you in the evening’, those words are not words of someone who is suicidal,” she said.
Reuters reported that the family’s lawyer, Javier Villalba, said he would be pursuing a second, independent autopsy before the initial autopsy had concluded its findings.
El Pais also reported that the family would be asking for a second autopsy to be carried out.
While the lawyer said it appeared McAfee had taken his own life he said he had no reason to believe the 75-year-old had been suicidal.
"I had constant telephone contacts with him," Mr Villalba told Reuters. "At no point had he shown any special worry or clue that could let us think this could have happened."
On Friday, McAfee’s widow blamed the US authorities for his death, claiming that the charges against him were “politically motivated”.
There has been significant speculation surrounding the mogul’s death. An Instagram account belonging to him posted an image of the letter “Q” after his death in an apparent reference to the Qanon conspiracy theory.
Upon his initial arrest, McAfee had previously tweeted from prison: “know that if I hang myself, a la Epstein, it will be no fault of mine,” in referencing the speculation surrounding the death of sex offender Jeffrey Epstein.
After subsequent months in prison, in April, McAfee had complained about "no entertainments – no escape from loneliness, from emptiness, from myself” while incarcerated, calling it the “most trying period of [his] life”.
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