KYIV, Ukraine (AP) -- Russian drone and missile strikes wounded at least 20 people in Kyiv, damaged residential buildings and caused blackouts across swathes of Ukraine early Friday, authorities said. A child was also killed in separate attacks in the southeast of the country.

In the heart of the Ukrainian capital, rescue crews pulled more than 20 people out of a 17-story apartment building as flames engulfed the sixth and seventh floors. Five people were hospitalized, while others received first aid at the scene, authorities said.

The Russian strikes had targeted civilian and energy infrastructure as Ukraine prepared for falling winter temperatures, President Volodymyr Zelenskyy said on social media.

Prime Minister Yuliia Svyrydenko also described the attack as "one of the largest concentrated strikes" against Ukraine's energy infrastructure.

Kyiv Mayor Vitali Klitschko said that Friday's attack knocked out power on both sides of the city, divided by the Dnipro River, while Ukraine's biggest electricity operator, DTEK, said that repair work was already underway on multiple damaged thermal plants.

The energy sector has been a key battleground since Russia launched its all-out invasion of neighboring Ukraine on Feb. 24, 2022.

Each year, Russia has tried to cripple the Ukrainian power grid before the bitter winter season, hoping to erode public morale. Ukraine's winter runs from late October through March, with January and February the coldest months.

Ukraine's air force said Friday that the latest Russian barrage included 465 strike and decoy drones, as well as 32 missiles of various types. Air defenses intercepted or jammed 405 drones and 15 missiles, it said.

In the southeastern Zaporizhzhia region, residential areas and energy sites were pounded with attack drones, missiles and guided bombs, killing a 7-year-old boy and wounding his parents and others, military administration officials said. A hydroelectric plant in the area was taken offline as a precaution, they said. ___

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