Ukrainian President Volodymyr Zelenskyy on Sunday made his first trip to the war-torn east part of the country since Moscow's invasion started.
After visiting Kharkiv, Zelenskyy announced that he had fired the northeastern city's security chief in a rare public rebuke, reported AFP.
Zelenskyy said the man was dismissed "for not working to defend the city from the first days of the full-scale war, but thinking only of himself," and that while others had toiled "very effectively", the former chief had not.
Although the president did not name the official, Ukrainian media reports identified him as Roman Dudin, the head of the Kharkiv region's SBU security service.
Earlier, Zelenskyy's office posted a video on Telegram of the president wearing a bullet-proof vest while viewing destroyed buildings in Kharkiv and its surroundings.
Russia, since failing to capture the capital Kyiv in the early stages of the war and then retreating from the Kharkiv area, has shifted its focus to the eastern Donbas region.
Its forces said on Saturday they had captured the town of Lyman in the contested region and were upping the pressure on the twin cities of Severodonetsk and Lysychansk.
Last week, Zelenskyy accused Russia of carrying out "an obvious policy of genocide" in Donbas.
Moscow's offensive in Donbas could end up leaving the region "uninhabited," he warned.
Zelenskyy had been based in Kyiv since Russian President Vladimir Putin launched his full-scale attack on Ukraine.
"In this war, the occupiers are trying to squeeze out at least some result," he said in a later Telegram post Sunday.
"But they should have understood long ago that we will defend our land to the last man," he added.
While one-third of the Kharkiv region remained under Russian control, "We will for sure liberate the entire area," continued Zelenskyy. "We are doing everything we can to contain this offensive."
The President described a scene of devastation in Severodonetsk, saying, "All critical infrastructure has already been destroyed... More than two-thirds of the city's housing stock has been completely destroyed."