KYIV, Ukraine — Russia stepped up its missile and drone attacks against Ukraine on Wednesday, killing students and other civilians, in a violent follow-up to dueling high-level diplomatic missions aimed at bringing peace after 13 months of war.

“Russia is shelling the city with bestial savagery,” President Volodymyr Zelenskyy wrote in a Telegram post accompanying video showing what he said was a Russian missile striking a nine-story apartment building on a busy road in the southeastern city of Zaporizhzhia. “Residential areas where ordinary people and children live are being fired at.”

At least one person was killed in the attack shown in the Zaporizhzhia video, apparently recorded by closed circuit TV cameras. Elsewhere, Moscow’s forces launched exploding drones before dawn, killing seven people in or near a student dormitory near Kyiv.

Ukrainian media showed several angles of the missile raining down on an apartment building across the street from a shopping mall in Zaporizhzhia, producing a huge plume of gray and black smoke, with bits of concrete flying into the air as cars whizzed by. Videos showed the violent outcome of the attack: charred apartments, flames and smoke billowing out of several floors of the buildings, and piles of broken concrete and shards of glass on the ground. Two children were among the wounded, said Zaporizhzhia City Council Secretary Anatolii Kurtiev, adding that 25 people needed hospital treatment, with three in critical condition.

Zaporizhzhia city is about 100 kilometers (60 miles) from the Zaporizhzhia Nuclear Power Plant, Europe’s largest which has come under threat during the war and has been shut down for months. The U.N.’s International Atomic Energy Agency reported the plant had suffered another loss of a backup external power source. Its six reactors still need power to cool nuclear fuel, and were relying on only a primary source Wednesday, the IAEA said.

Russia has denied targeting residential areas even though artillery and rocket strikes hit apartment buildings and civilian infrastructure daily. Russian officials have blamed Ukrainian air defenses for some of the deadliest strikes on apartments, saying the deployment of air defense systems in residential areas puts civilians at risk. Russia sometimes also claims Ukraine is hiding military equipment and personnel in civilian buildings.

The war, which Russia started Feb. 24, 2022, has evolved in two main directions: a front line mainly in eastern Ukraine, centered around the city of Bakhmut, and periodic Russian missile and drone strikes nationwide. In addition, periodic — although unconfirmed — Ukrainian sabotage attacks have been launched across the border into Russia. The front-line fighting largely stalemated over the winter, with expectations of major offensives by both sides expected in more favorable spring weather.

Earlier Wednesday, a drone attack damaged a high school and two dormitories in the city of Rzhyshchiv, south of the Ukrainian capital, officials said. It wasn’t clear how many people were in the dormitories at the time. The body of a 40-year-old man was pulled from the rubble on one floor, according to regional police chief Andrii Nebytov, adding that more than 20 people were hospitalized. A second fatality was reported later. Video showed what appeared to be a bloodied sneaker and a green ball on the ground near a damaged building, whose top floor was ripped off at a corner.

The attacks occurred as dueling diplomatic missions were winding down. Japanese Prime Minister Fumio Kishida left Kyiv after meeting Zelenskyy to support Ukraine. Chinese leader Xi Jinping left Moscow after meeting with Russian President Vladimir Putin about Beijing’s peace proposal, which the West has rejected as a non-starter. No progress toward peace was reported.

U.S. National Security Council spokesperson Adrienne Watson noted the violent turn of events.

“Just one day after Russia called for peace, Russia is attacking Ukrainian homes as part of its brutal war,” she said in Washington. “What Russia is doing is horrific — and we are committed to continuing to help Ukraine defend itself against this Russian aggression.”

The drone barrage and other Russian attacks on civilian infrastructure also drew a scathing response from Zelenskyy.