Russia prison inmates march for VE Day
Russian prisoners at three jails in and around St Petersburg are seen marching to mark Victory Day, when World War Two in Europe ended.
The video, commissioned by the Directorate of the Federal Prisons Service (UFSIN), shows them forming the words "Thank you for victory". They also release gold and black balloons - the colours of the Russian military's St George flag.
Russia will hold a vast military parade on 9 May honouring the Soviet Red Army's triumph over Nazi Germany in 1945.
UFSIN spokeswoman Yulia Aleshina told the BBC that the inmates involved in the flashmob volunteered for it. They were in jail for relatively minor offences, she added.