Shortly after Russian troops seized control of the Chernobyl nuclear power plant, radiation sensors in the Chernobyl Exclusion Zone (CEZ) began reporting alarming spikes in radiation levels. Ukrainian authorities blamed the spikes on Russian military equipment stirring up radioactive dirt. However, security researcher Ruben Santamarta and other experts doubted this explanation. Santamarta discovered distinct patterns in the data produced by the sensors, indicating that it had likely been manipulated. The International Atomic Energy Agency (IAEA) and Greenpeace conducted investigations, but their focus was not on the cause of the spikes. It remains unclear why the data from the sensors stopped getting updated and whether the spikes were genuine or false.
https://zetter.substack.com/p/radiation-spikes-at-chernobyl-a-mystery