On Wikipedia the "Tchernobyl: 4000 deaths" false claim published in a press release was relayed by an anonymous contributor, albeit it falsely stated that the underlying report was definitive, encompassing all illnesses and published by UN bodies.
At least a warning was proposed, without any effect.
Then, 7 months later, after release of the real definitive UN report (9000 deaths in a subset of the population and for only a family of illnesses) some history-rewriting took place, by simply replacing ''4,000'' with ''9,000', as if ''9,000'' was published since Sept. 2005, and without any account of the new perimeter (solid cancers and subset of exposed population, instead of grand total, and real UN report).
No one detailed, in the Wikipedia article, the disinformation nor the plain fact that no rectifying was published by the during or after the 7-months long period between the draft report and the UN version.
Then a talk led to a partial fix. But some dis (or mis)-information stays there, and nobody seems to care.
Worse: on Wikipedia (French edition) some try to conceal or minimize the disinformation campain.
Here is a complete account, with all pointers to evidence.