Russia launched a major overnight missile and drone assault on Kyiv and surrounding regions on Wednesday, damaging energy infrastructure and killing at least four people as Ukraine braces for the onset of winter.

Ukrainian officials said the attack targeted energy facilities in Kyiv and other parts of the country, causing power outages and fires and prompting emergency crews to work through the morning to restore electricity.

Prime Minister Serhii Koretskyi described the assault as the largest combined attack on Ukraine's energy infrastructure since the end of the last heating season.

"Since the summer, there has been practically no day when the enemy has not attacked energy infrastructure," Koretskyi said. "But such a massive and combined attack has occurred for the first time since the end of the last heating season."

Ukraine's largest private energy company, DTEK, said its facilities were damaged during the overnight strikes. The company said it had restored electricity to about 8,000 customers on Kyiv's left bank, while emergency crews continued repair work.

State-owned grid operator Ukrenergo also reported power outages in Kyiv, Kyiv region and other parts of the country. It urged consumers to postpone using high-power electrical appliances while the system was being stabilized.

President Volodymyr Zelensky said energy infrastructure in Kyiv and the surrounding region was the main target of the attack, stressing the importance of strengthening Ukraine's air defenses ahead of winter.

"Each interceptor missile really saves lives. And the closer to winter, the more such protection is needed," Zelensky said. "We must do everything to ensure that Russia's bet on ballistic and drone terror does not play out."

Ukraine's Air Force said Russia attacked the country with 188 drones, including 86 jet-powered drones, as well as Zircon, Oniks and Iskander missiles. Ukrainian forces said they shot down or suppressed 155 drones and five missiles.

The overnight attack caused casualties in several parts of Kyiv and the surrounding region.

Ukraine's State Emergency Service said two women were killed in Kyiv's Sviatoshynskyi district, where several homes were damaged. Another person was killed when a warehouse was struck in the Solomianskyi district, according to the Kyiv City Military Administration.

In neighboring Kyiv region, a child was found dead under the rubble of a house in Vyshhorod. A man and a woman were also injured in the attack. Ukrainian officials said at least seven people were injured overall in Kyiv and the surrounding area.

Kyiv Mayor Vitali Klitschko said emergency services were responding to fires and damage across the capital. An unspecified non-residential building and a warehouse caught fire in the Podilskyi district, while debris fell on the grounds of an unspecified Western embassy in the Shevchenkivskyi district.

Authorities also reported power outages in parts of Kyiv, while thick smoke spread across the city. The State Emergency Service advised residents to keep their windows closed because of the smoke.

In Bucha, northwest of Kyiv, 11 vehicles, two warehouses and three homes were damaged, according to regional officials.

Russian state news agency TASS, citing Russia's Defense Ministry, reported that the strikes hit a communications center in Kyiv, energy facilities in the Kyiv region and infrastructure at the port of Izmail. Russia has repeatedly said its strikes are directed at Ukrainian military and strategic infrastructure.

Ukrainian officials did not immediately confirm Russia's claim that the Trypilska thermal power plant, the largest power plant in Kyiv region, had been struck. Kateryna Pop, a spokeswoman for the Kyiv City Military Administration, said additional protection measures were being implemented to preserve the city's energy capacity and maintain stable supplies of heating and hot water.

The attack came after a series of increasingly frequent Russian strikes on Kyiv in recent weeks. Since August, Russia has repeatedly launched large waves of drones against the capital, including daytime attacks. Ukrainian officials say the attacks have increasingly involved jet-powered drones and ballistic missiles, placing additional pressure on the country's air-defense network.

More than a dozen explosions were heard in Kyiv shortly before 3 a.m. local time, according to journalists on the ground. The blasts followed warnings from Ukraine's Air Force that ballistic missiles were approaching the capital. Additional explosions were heard at around 3:40 a.m.

The latest assault followed another series of strikes on Kyiv on Sept. 28 and 29. On Sept. 28, Russian drones struck several districts of the capital, killing two people and injuring 26, according to Ukrainian officials. The attacks damaged non-residential buildings and set fire to a building belonging to Ukraine's National Academy of Sciences.

The continuing attacks have heightened concerns about Ukraine's energy system as the country heads toward the winter heating season. Ukrainian authorities have been preparing additional protection for critical infrastructure while seeking more air-defense systems to defend power facilities and major cities.

The full extent of the damage from Wednesday's attack was still being assessed.

Russia's latest assault also came amid continued diplomatic efforts to end the war, but no comprehensive ceasefire has been reached and fighting has continued across Ukraine. (ILKHA)