Russian missile strikes on a Kyiv residential building killed 24 people during the largest aerial barrage since the invasion began.Ukraine retaliated by targeting a Russian oil refinery in Ryazan while both nations simultaneously completed a prisoner exchange with UAE assistance.Global leaders condemned the aggression as experts highlighted how recently manufactured components indicate persistent Russian sanctions evasion.Kyiv observed a national day of mourning to honor the victims as international officials discussed establishing a formal war crimes tribunal.