Russian forces unleashed a nighttime barrage of more than 50 cruise missiles and explosive drones at Ukraine’s power grid Wednesday, targeting a wide area in what President Volodymyr Zelensky called a “massive” attack on the day the country celebrates the defeat of Nazism in World War II.

Russia launched aerial attacks on energy facilities throughout Ukraine early Wednesday, targeting seven regions with more than 50 missiles as well as drones, President Volodymyr Zelenskyy said. Russia consistently targets Ukraine’s energy infrastructure.

Russia also hit the two power plants run by private firm DTEK - one in Ladyzhyn in central Ukraine and another in Burshtyn in the west. DTEK said at the time, without specifying which, that some of its facilities had been destroyed totally and others were running at around 50% capacity.