Invisible prisoners — the struggle to free thousands of Ukrainians in Russian captivity

Warning: This article contains graphic descriptions.

Vitalii Atamanchuk was the archetypal man of the Donbas, the industrial heartland that stretches across eastern Ukraine.

He spent more than 20 years toiling in a coal mine. In 2000, he retired, but found the life of a pensioner dull. He went back to