(NewsNation) — Civilians and soldiers celebrated over the weekend in northeastern Ukraine, raising their country’s flag again, after what may be the worst setback for Russia since their invasion in February.

In a speech to his country late Sunday, which marked 200 days of war, Ukraine’s President Volodymyr Zelensky was defiant, asking of Russia, “Do you still think you can intimidate, break us, force us to make concessions?”

The update, however, came as Russian forces responded to the counteroffensive with an attack of their own, targeting power stations and other infrastructure Sunday in what Zelensky called acts of terrorism.

One missile strike on a power station Sunday night sparked a major fire and plunged Kharkiv into darkness for hours. In the blackness, another missile slammed into a residential building at around midnight, collapsing part of it and killing one person, local officials said.

But officials said power and water were restored to 80% of the region.

The missile strikes killed at least one person near Kharkiv, Ukraine’s second largest city.

“It’s dangerous to live in Kharkiv, every day is dangerous. It’s dangerous during the day and night,” said Kateryna Protsenko, a 29-year-old veterinarian living across the street from the apartment building.

“The nights are sleepless, but anyway you continue to live because you have a family and you need to survive and work somehow,” she said, visibly shaken at the sight of the building, which has a gaping hole where part of the third story used to be.

The building’s facade had peeled off and piles of rubble lay strewn on the ground, mixed with the twisted metal shrapnel of the missile. On the building’s second story, a closet stood suddenly exposed, a single coat hanger dangling precariously from its rail.

Protsenko said she couldn’t leave Kharkiv — she needed to work, and there were still sick animals to treat.

“So you live where you can live, and you understand that today you are alive but you can be gone in a minute,” she said.

More explosions sounded out in the middle of the day Monday, with a police administrative building set on fire by a strike that killed one person in a neighboring building.

“Russia carried out a rocket attack against a peaceful city, where peaceful people live, just the same as the people living in the United States of America, or anywhere else in the world, who go to school, have their ordinary lives, raise their children,” Kharkiv regional police Chief Volodymyr Timoshko said.

Behind him, firefighting crews clambered up ladders with hoses, dousing the flames leaping out of the top story of the building as choking smoke billowed out over the city.

Timoshko said authorities believed the building was hit by a rocket from a Smerch multiple rocket launcher.

“It’s quite a powerful weapon which is used for mass destruction, I repeat, mass destruction of the population,” he said. “They are using it during the daytime in the city center, the city which is living a normal life.”

The hasty pullout by Russia led Ukrainian soldiers to take stock of the tanks, weapons and ammunition left behind.

So far, the Kremlin is dodging questions about this latest failure despite rare criticism from military bloggers and political commentators at home.