Kyiv : Russian forces have stepped up their bombardment of Ukraine’s besieged port city of Mariupol, bombing an art school where officials say 400 people had taken shelter, Khaleej Times reported on Tuesday. Soon after the attack, Russia demanded that Ukrainians holed in the besieged city lay down their arms in exchange for safe passage out of town, which was rejected by the Ukrainian. Mariupol has continued to bear the brunt of the Russian attacks. Meanwhile, the governor of Ukraine’s Zaporizhzhia region accused the Russian forces of attacking buses evacuating civilians from front line areas injuring four children. Russian forces have ramped up their sorties over and near Ukraine, flying more than 300 missions in the past 24 hours, with Kyiv also increasing its own air operations in a bid to dent the Russian superiority in the skies reports said. The mayor of Kyiv said on Monday that he will be introducing longer curfew in the city because the authorities expect further shelling by Russian forces. Meanwhile, Ukrainian President Volodymyr Zelensky said on Monday that a meeting with Russian counterpart Vladimir Putin “in any format” is needed to end the war in Ukraine. In his nightly address to the nation, Zelensky said Ukraine is interested in peace, and that ongoing talks with Russia are “necessary”.