The Russian missile that struck Wednesday in eastern Ukraine turned an outdoor market into a fiery, blackened ruin where weeping civilians looked for loved ones among the mangled, burned bodies scattered across the ground. The blast in the town of Kostiantynivka killed 17 people and wounded at least 32 in one of Russia’s deadliest strikes on civilians in months, Ukrainian officials said. “There was no military target here. This is a peaceful neighborhood in the city center,” Stefan Slovak, who lives in Kostiantynivka, said in a trembling voice. Behind him were the remnants of the market, where charred bodies could...