Mykhailo Poperechnyuk was driving towards the town of Nikopol, in southern Ukraine, earlier this month when he saw a barrage of Russian rockets streaking across the night sky. The missiles were fired from what may be the most impregnable Russian positions along the entire front line: those around the Zaporizhia nuclear power plant just 5km away on the other side of the Dnipro River.

The Russian army seized the vast facility — the biggest in Europe, with six 950MW reactors — in the early weeks of its invasion, destroying a training office during the assault despite the obvious risks of damaging the plant and radiation leaks.

Since then, Ukrainian officials say, the Russians have stationed 500 troops and heavy weapons within the perimeter — in breach of international energy conventions — and are using the reactor blocks to protect against retaliatory fire.

“Imagine how cynical and immoral the Russians are,” said Poperechnyuk, a businessman and activist who is a member of Ukraine’s territorial defense forces. “They are putting their artillery just behind the reactors so Ukrainian armed forces cannot respond. ”

The people of Nikopol, a down-at-heel Russian-speaking steel town made up of factories and Soviet-era housing blocks, now live in the shadow of a power plant that has been turned into a Russian fortress. And there is little the countrys military can do either to attack or defend.

Since the salvo Poperechnyuk witnessed on July 14 there have been almost nightly Russian bombardments, frightening and exhausting residents — just as other towns and cities in the eastern Donbas region and southern Ukraine are