"Unfortunately, Volyn was targeted in the enemy's massive attack," he wrote. "Emergency power outages have been introduced after a series of strikes recorded in Oblast." Read also: North Korea prepares to supply more ballistic missiles to Russia,

The co-ordinated assault unfolded over several hours with waves of drones and missiles flying across the country.

Russia conducted a “massive” missile and drone attack against Ukraine’s energy infrastructure on Thursday, officials said, adding to fears that the Kremlin aims to cripple the country's power generation capacity before winter.