Several musicians and celebrities shared their condolences early Monday morning after a gunman in a Las Vegas hotel opened fire on a country-music concert Sunday night. During Jason Aldean’s concert for the Route 91 Harvest Country Music Festival, the shooter fired at the crowd, leaving more than 50 dead and wounding over 200 people. Police identified the gunman as Stephen Paddock, 64. On Instagram, Aldean called the night “beyond horrific,” and said his family and crew were safe. Others — including Barack Obama, Mariah Carey, and Céline Dion — shared their condolences online.