MIAMI (CBS4) – Social media giant Twitter was buzzing with rumors that former Cuban leader Fidel Castro is dead, or very close to it.

According to CBS4 News partner The Miami Herald, the trend began last week and whipped up such a frenzy, international news organizations and bloggers began to investigate if the claims were true.

“My phone hasn’t stopped ringing. Everybody is asking me if it’s true that Fidel Castro is very sick,” was part of the message Cuban dissident and blogger Yoani Sánchez wrote on her Twitter account around 3 p.m. Tuesday. “I DON’T KNOW, and if it were true, we Cubans would be the last ones to find out.”

An Internet site in Argentina blamed a Chilean website for starting the rumor, which they denied.

Naked Security, which investigates hacking an malware claims looked into the matter and determined that the Chilean site was not responsible for the false news, but rather a hacker posing as an administrator of the website.

The company says the news was disseminated through an email with the subject “Fidel Castro is Dead” which contained a photo of the communist leader is a casket. The photo was a fake.

It was also determined that the message was linked to programs designed to attack software.

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