As the staging ground for an assault on the Ukrainian capital of Kyiv, the Chernobyl Exclusion Zone, one of the most toxic places on Earth, was probably not the best choice. But that did not seem to bother the Russian generals who took over the site in the early stages of the war.

"We told them not to do it, that it was dangerous, but they ignored us,” Valeriy Simyonov, chief safety engineer for the Chernobyl nuclear site, said in an interview.

Apparently undeterred by safety concerns, the Russian forces tramped about the grounds with bulldozers and tanks, digging trenches and bunkers — and exposing themselves to potentially harmful doses of radiation lingering beneath the surface.