Blame laid on Anatoly Chubais, the head of UES, as a criminal investigation into the failure is launched. UES cites substation fire and heavy demand

A massive cascading failure saw power outages for several hours across large parts of Moscow and four surrounding regions leaving as many as 2 million people without electricity.

The failure is centred round the Chagino substation in Kapotnya, south of Moscow that was damaged by fire the previous evening and broke down as morning demand rose. The outage began in the city before spreading to the Moscow, Tula, Kaluga and Ryazan regions. Following the failure of the Chagino substation, which had been installed in 1963, other substations became overloaded and automatically shut down.

President Vladimir Putin blamed Unified Energy Systems (UES) for the outage and called for its chief Anatoly Chubais to take responsibility for the outage. The Prosecutor General’s Office has already opened an investigation into “criminal negligence” by UES management and was expected to question Chubais within hours of the incident.

Chubais, meanwhile, has been quoted as saying “UES and its chairman are responsible for energy supply. I don’t take responsibility off myself,” although he did refer to record temperatures in relation to the incident.