Ukraine's military says that its forces have beaten back a Russian attack in the southern region of Kherson, while shelling by Moscow's forces in the northeastern city of Kharkiv killed seven people and wounded 16.
Ukrainian President Volodymyr Zelenskiy called the Kharkiv shelling, which hit a dormitory, "vile and cynical."
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"Pain for Kharkiv. Rocket attack.... On the dormitory.... The building was completely destroyed," Zelenskiy wrote on Telegram. "A vile and cynical attack on civilians that has no justification and demonstrates the powerlessness of the aggressor. We will not forgive, we will take revenge."
In southern Ukraine, Kyiv's forces repelled an attempted advance by Russian forces near the town of Bilohirka, northeast of Kherson, Ukrainian military analyst Oleh Zhdanov said.
The southern district of the Operational Command of the Ukrainian armed forces said its forces killed 29 "occupiers" and destroyed artillery, armored vehicles, and a military supply depot.
The claims could not be independently confirmed.
"Russian forces have achieved only minimal advances, and in some cases we have advanced, since last month," Ukrainian presidential adviser Oleksiy Arestovych said in a video message. "What we are seeing is a 'strategic deadlock.'"
Meanwhile, Russia's RIA Novosti news agency on August 17 quoted sources as saying the commander of the Black Sea Fleet, Igor Osipov, had been replaced with a new commander, Viktor Sokolov.
The move, if confirmed, would mark one of the most prominent dismissals of a Russian military official so far in the almost six-month war.
Russia's Black Sea Fleet has suffered several humiliations since the invasion of Ukraine on February 24, including the sinking in April of its flagship, the Moskva, a missile cruiser, with Neptune missiles.
Most recently, military bases and ammunition depots in the past week in the Russian-occupied region of Crimea were hit by explosions over the past week.
Britain's Ministry of Defense said in its daily intelligence bulletin on August 18 that the altogether poor performance of Russian forces since the start of the invasion could be at least partially caused by the commanders' failure to enforce low-level battle discipline.
British intelligence pointed to the Russian forces' lack of training in properly fitting and maintaining tank armor -- a deficiency first noticed during the first Chechen War of 1994 -- as likely the main reason for Moscow's heavy losses in tanks and armored vehicles.