KYIV — Russian forces unleashed 99 missiles and drones in a fourth massive attack against Ukrainian energy infrastructure in the past 10 days.

Three fossil fuel-fired power plants were seriously damaged, Ukrainian energy company DTEK said in a statement.

“All night, Russia has ruthlessly launched missiles & drones against Ukraine’s energy infrastructure — now all of Ukraine is under air alert,” tweeted U.S. Ambassador to Ukraine Bridget Brink. “Our assistance is needed now.”

Ukrainian air defense forces were able to shoot down 84 out of the 99 missiles and drones Russia fired on Ukraine in the night on Friday, Ukrainian Air Force Commander Mykola Oleshchuk said in a statement.

The assault involved 60 drones and 39 missiles of different types, including three hypersonic Kh-47M2 Kinzhal air-launched ballistic missiles. The missiles originated from the Ryazan, Kursk and Belgorod regions of Russia, as well as from the occupied Crimean Peninsula. 

“The enemy attacked energy facilities in the Dnipropetrovsk, Cherkasy, Kirovohrad, and Ivano-Frankivsk regions. Thermal power plants and substations were damaged, leaving utility services, local industry, and population without power,” the Ukrainian Energy Ministry wrote.

Power shortages were caused by hostilities in the Vinnytsia, Donetsk, Kharkiv and Kherson regions, reported state energy company Ukrenergo.

This year, Russia’s attacks on energy infrastructure have become more precise and deadly, DTEK operational director Dmytro Sakharuk said at a conference in Kyiv on Thursday.

“The accuracy of the missiles is impressive,” Sakharuk said. If earlier they landed 100 meters to 200 meters from the target, more recently this has been about 1 meter, he said.

“The damage is tremendous. No roofs, no equipment, just a plain field left at our facilities after the strikes … scorched earth,” he added.