KYIV, Ukraine — The Ukrainian military said Wednesday that it struck a fuel storage depot deep inside Russia, causing a huge blaze at the facility that supplies an important Russian air base. Russian officials acknowledged a major drone attack in the area, and said that authorities had set up an emergency command center to fight the fire.

It reported multiple explosions and a big fire at "Kristal" oil depot, which it said provided fuel to the "Engels-2" military airfield, where Russia's strategic bomber fleet is based. "The strike of the oil depot creates serious logistical problems for the strategic aviation of the Russian occupiers and significantly reduces their ability to strike at peaceful Ukrainian cities and civilian objects,

Ukrainian drones attacked the Russian cities of Saratov and Engels, where Russia has an air base for its fleet of strategic bomber planes, the regional governor said on Wednesday. Governor Roman Busargin said the two cities had been subject to a mass drone attack and there was damage to an industrial site.

Ukrainian drones struck deep inside Russia overnight and attacked the Saratov region, causing a major fire in the city of Engels, the local governor said on Wednesday.

Russia launched doxens of drones against cities and towns in southern and eastern Ukraine overnight killing three people and injuring at least 23, Ukrainian authorities said.