FILE - An apartment building explodes after Russian army tank fire in Mariupol, Ukraine, March 11, 2022. A Ukrainian paramedic who won praise for his bravery in the siege of Mariupol now works to save soldiers on the front lines of Ukraine's war with Russia. Serhiy Chornobryvets barely slept and rarely took off his red paramedic uniform as he raced around his hometown of Mariupol, rescuing those wounded by the Russian bombs and shells that pummeled the southern Ukrainian city. (AP Photo/Evgeniy Maloletka, File)