City Council Says Thousands of Ukrainians Forcibly Taken from MariupolOfficials in Ukraine have yet to release the death toll following a Russian missile attack Friday on a military base where soldiers were sleeping in barracks, now destroyed, in the southern Ukrainian city of Mykolaiv. "We aren't allowed to say anything because the rescue operation isn't over and the families haven't all been informed," military spokesperson Olga Malarchuk told Agence France-Presse. One soldier told AFP that 50 bodies have been found, while another said there could be as many as 100 dead under the rubble. Mykolaiv is located 130 kilometers from the strategic military port of Odesa. An art school where about 400 people had found shelter in Ukraine’s besieged port city of Mariupol has been bombed by Russian forces. Mariupol’s city council said Sunday that the building was destroyed in the attack. Information about survivors was not immediately available. Thousands of residents of Mariupol have been forcibly taken from their homes, the city’s council said Saturday. "Over the past week, several thousand Mariupol residents have been taken to Russian territory," according to a Mariupol city council statement on its Telegram channel. "The occupiers illegally took people from the Livoberezhny district and from the shelter in the sports club building, where more than a thousand people (mostly women and children) were hiding from the constant bombing." "It is hard to imagine that in the 21st century people can be forcibly taken to another country," Mariupol Mayor Vadym Boichenko said in the statement. "What the occupiers are doing today is familiar to the older generation, who saw the horrific events of World War II, when the Nazis forcibly captured people," Boichenko said. Ukrainian President Volodymyr Zelenskyy said in his nightly address Saturday that Russia’s behavior in Mariupol would "go down in history of responsibility for war crimes.” Zelenskyy has called for comprehensive peace talks with Moscow. “The time has come for a meeting, it is time to talk,” Zelenskyy said. “The time has come to restore territorial integrity and justice for Ukraine. Otherwise, Russia's losses will be such that it will take you several generations to recover." Zelenskyy’s appeal for another round of talks came one day after Russia's lead negotiator said the sides have moved closer to agreement on the issue of Ukraine dropping its bid to join NATO. Vladimir Medinsky said Friday the two countries also are "halfway there" on the question of Ukraine adopting neutral status. Ukrainian negotiator Mykhailo Podolyak tweeted, "Our positions are unchanged. Cease-fire, withdrawal of troops & strong security guarantees with concrete formulas." Russian Foreign Minister Sergey Lavrov said Moscow expected its invasion of Ukraine to end with a comprehensive agreement on security issues, including Ukraine’s neutral status, according to Russia’s Interfax news agency. Russia said Saturday that its hypersonic missiles had destroyed an underground depot for missiles and ammunition Friday in Ukraine’s western Ivano-Frankivsk region. Russian news agencies said it was the first time it used the advanced weapons system in Ukraine since it invaded on Feb. 24. Russia’s hypersonic missiles claims were not independently confirmed. A Ukrainian air force spokesperson verified the attack, but said Ukraine had no information on the type of missiles used. Russia still stalled The latest British defense intelligence assessment of the conflict, made Saturday, concluded that Russia has been forced to “change its operational approach and is now pursuing a strategy of attrition.” “This is likely to involve the indiscriminate use of firepower resulting in increased civilian casualties,” the ministry warned. Russian troops have failed to seize control of the Ukrainian capital, Kyiv, a major objective of the Kremlin, even as the invasion enters its fourth week. Ukraine’s National Police said in a statement Saturday on Telegram that Russia was attacking the northwestern suburbs of Kyiv, while the regional Kyiv government reported the city of Slavutych, north of Kyiv was “completely isolated.” Also Saturday, Ukraine said that a Russian general had been killed in attacks on an airfield outside the southern city of Kherson, the fifth senior Russian officer killed since the invasion began. Humanitarian corridors, casualties In other developments, humanitarian corridors were opened Saturday, allowing a total of 6,623 people to evacuate from various Ukrainian cities, according to Kyrylo Tymoshenko, deputy head of the president's office. He reported online that 4,128 of those people escaped from Mariupol. There are plans to open more corridors Sunday. The United Nations human rights office reports that more than 847 civilians had been killed and upward of 1,399 have been wounded as of Friday, while warning the actual count likely is significantly higher. The Ukrainian prosecutor general’s office said 112 of those killed were children. Officials in Kyiv said Saturday that since the start of the invasion more than three weeks ago, 228 people had been killed in the capital city, including four children. In a statement, the administration reported 912 people have been wounded, though all these figures remain unconfirmed by outside sources. Nearly 3.3 million people have fled the war in Ukraine, according to U.N. estimates. The U.N. migration agency said Friday that in addition to those who have left the country, nearly 6.5 million people have been displaced inside Ukraine and that another 12 million people have been stranded or unable to leave parts of Ukraine because of heightened security risks or a lack of resources. VOA's White House Bureau Chief Patsy Widakuswara, congressional correspondent Katherine Gypson and U.N. correspondent Margaret Besheer contributed to this report. Some information also came from The Associated Press, Agence France-Presse and Reuters.