I wanted to find out how the media could mess up a simple factual story on whether or not a famous person had died. It proved to be quite difficult to google for "Gorbachev death/died/dead misreported/erroneous/false" and lots of other variations; I kept getting hits on current news. But I finally found a report from 2013 here:

https://www.spiegel.de/international/world/false-story-about...

The state-run news agency RIA Novosti in Moscow that published the erroneous story for just 5 minutes blamed it on hackers. But the false news spread widely from there.