More than 1,000 Ukrainian Marines have been handed over to the besieged port of Mariupol, the Russian Defense Ministry said on Wednesday on the main target of Moscow in the eastern Donbass region, which it has not yet taken control of. If the Russians occupy the Azovstal industrial area, where the Marines are hiding, they would have full control of Mariupol, Ukraine’s main port of the Azov Sea, allowing Russia to strengthen a land corridor between the eastern controlled the separatists and the Crimea that he occupied and annexed in 2014. Surrounded by Russian troops for weeks and at the center of some of the fiercest fighting in the war, Mariupol would be the first major city to fall since Russia invaded Ukraine on February 24. The battle for the industrial heart of Donbass is likely to determine the course of the war. The Russian Defense Ministry said 1,026 soldiers from Ukraine’s 36th Marine Brigade had surrendered, including 162 officers. Ukraine’s general staff said Russian forces were attacking Azovstal and the port, but a Defense Ministry spokesman said he had no information about any surrender. Reuters reporters accompanying Russian-backed separatists saw flames erupt from the Azovstal region on Tuesday. On Monday, the 36th Marine Brigade said it was preparing for a final battle in Mariupol that would result in death or captivity as its troops ran out of ammunition. Thousands are believed to have been killed in Mariupol and Russia has mobilized thousands of troops in the area for a new offensive, said Ukrainian President Volodymyr Zelensky. Ukraine says tens of thousands of civilians have been trapped inside the city with no way to bring food or water, and accuses Russia of blocking aid convoys. Chechen leader Ramzan Kadyrov, an ardent supporter of Russian President Vladimir Putin, urged the remaining Ukrainians who had taken refuge in Azovstal to surrender. “At the moment there are about 200 injured people in Azovstal who can not get any medical help,” Kadyrov told the Telegram. “It would be better for them and everyone else to stop this useless resistance and go home to their families.” Russian television showed photos, he said, of marines being delivered to Illich Iron and Steel Works in Mariupol on Tuesday, many of whom were injured. MURAT YUKSELIR / THE GLOBE AND MAIL, SOURCE: GRAPHIC NEWS It showed what he was saying as Ukrainian soldiers were walking down a street with their hands in the air. One of the soldiers appeared to be holding a Ukrainian passport. Ukraine’s Deputy Defense Minister Hanna Malyar said there was a high risk of Russia using chemical weapons, echoing earlier warnings by Zelensky, who told the Estonian parliament on Wednesday that Russia was using phosphorous bombs to terrorize terrorists. He did not provide information and Reuters could not independently verify his claim. The production, use and storage of chemical weapons is prohibited under the 1997 Chemical Weapons Convention. White phosphorus, although condemned by human rights organizations, is not banned. Russia denies using chemical weapons, saying it had destroyed its last stockpile of chemicals in 2017. The Moscow invasion of Ukraine, the largest attack on a European state since 1945, led to more than 4.6 million people fleeing abroad, killing or injuring thousands and leaving Russia increasingly isolated on the world stage. The Office of the Prosecutor General of Ukraine announced that 191 children were killed and 349 were injured since the beginning of the invasion. The Kremlin says it has launched a “special military operation” to demilitarize and “demilitarize” Ukraine. Kyiv and its Western allies dismiss it as a false pretext for an unprovoked attack. The presidents of Poland, Lithuania, Latvia and Estonia arrived in Kyiv on Wednesday to meet with Zelenski, the Polish leader’s office said. Estonian President Alar Karis had earlier tweeted that they were offering political support and military assistance. The four are joined by a growing number of European politicians who have been visiting the Ukrainian capital since Russian forces withdrew from the north earlier this month. US President Joe Biden has said for the first time that Moscow’s invasion of Ukraine was tantamount to genocide, with Putin saying Russia would continue to operate “rhythmically and calmly” and achieve its goals. Russia has denied that it targeted civilians and said Ukraine and the West’s allegations of war crimes were fabricated. Many cities from which Russia has retreated to northern Ukraine were filled with the bodies of civilians killed in a campaign of killings, torture and rape, according to Kyiv. Ukraine’s Interfax news agency on Wednesday, citing the chief of police of the Kiev region, said 720 bodies had been found in the area around the capital, with more than 200 people missing. The General Staff of the Armed Forces of Ukraine stated that Russian forces are carrying out attacks on civilian infrastructure in the Kharkiv region in the northeast and in the Zaporizhzhia region in central Ukraine. At least seven people have been killed and 22 injured in Kharkov in the past 24 hours, Governor Oleh Synegubov said. A 2-year-old boy was among those killed in the 53 artillery or rocket attacks carried out by Russian forces in the area, he said in an online post. Reuters could not independently verify the information. Russia denies targeting civilians. Putin used his first public comments on the conflict in more than a week on Tuesday to express confidence that his goals would be achieved. Zelensky mocked Putin in an early-morning speech: “How could a plan to kill tens of thousands of their own soldiers in just over a month of war be implemented?” Ukraine said on April 11 that tens of thousands of people had probably been killed in the Russian attack on the southeastern city of Mariupol. Reuters Our Morning and Afternoon newsletters are compiled by Globe editors, giving you a brief overview of the day’s most important headlines. Register today.