Viktor Sayenko was born in 1988 in Dnipropetrovsk, now Dnipro, and grew up in the same middle-class district as Igor Suprunyuck and Alexander Hanzha. His father was a senior figure in the local trades union organisation.
Between June 25 and July 16, 2007, he and Suprunyuck killed twenty-one people across the city and its outskirts, attacking whoever they came across with hammers and steel bars: pregnant women, elderly people, children, homeless men. Eighteen of the killings were charged against Sayenko personally. Nothing was taken in most cases and the victims had no connection to them or to each other. Ukrainian reporting called the pair the Dnepropetrovsk Maniacs.
They photographed the bodies and recorded video of at least one killing, and one of those recordings was leaked from the case file in 2008 and circulated internationally.
They were arrested on July 23, 2007 after trying to sell a stolen telephone. Sayenko was convicted on February 11, 2009 and sentenced to life imprisonment. Hanzha, who had taken part in earlier robberies but not the killings, received nine years.
Both men were nineteen. Neither has given an explanation that the Ukrainian court or anyone since has found coherent.