Nekhoroshev was the former editor of Moskovsky Korrespondent, the newspaper that published the 2008 report, the Daily Mail reported.
The front page of Moskovsky Korrespondent that in 2008 reported that Putin planned to divorce his then wife.
After the report was released the Moskovsky Korrespondent closed, which was then owned by businessman and former KGB agent Alexander Lebedev.
Despite being regarded as knowledgeable about mushrooms, it appears Nekhoroshev may have misidentified the species, Metro UK reported.
There is no evidence pointing to Putin being responsible, but many people who oppose the leader have died in suspicious circumstances, like former opposition leader Alexei Navalny, who died in an arctic prison in 2024.
One online commenter on the news dug up an old Russian joke:
“A businessman died from mushroom poisoning,” a man said.
“But why his face is all bruised?!” asked another.
“Well, he didn’t want to eat them,” the man said.
Nekhoroshev died on June 19 in Riga, Latvia’s capital, where he had lived for 11 years as a political refugee. Photo / Grigory Nekhoroshev
Fellow Russian journalist Bozhena Rynska, who is also based in Latvia, described his death as “incomprehensible”, Metro UK reported.
Nekhoroshev had labelled himself a “personal enemy” of Putin after revealing details of the Russian leader’s private life.
At the time, Putin responded to the reports condemning “those who with their snotty noses and erotic fantasies prowl into others’ lives”, according to the Daily Mail.
The Russian leader has never formally confirmed the relationship with Kabaeva, now 43, although the pair are believed to have two children together, Ivan, 11, and Vladimir, 7.
Latvian authorities are yet to make any public statement on the death, with an autopsy to be carried out.