The cause of the crash—which also killed Iranian Foreign Minister Hossein Amirabdollahian, the governor of Iran’s East Azerbaijan province, and others—is pending investigation. But any official finding will be open to interpretation—like the fireworks that erupted in the streets over Tehran on Sunday night: were they celebrating the eve of the holiday marking the birth of Reza, known as the 8th Imam? Or the death of Raisi, the notoriously hardline President? ...

“Raisi’s death would create a succession crisis in Iran,” Karim Sadjapour, a senior fellow at the Carnegie Endowment for International Peace, told TIME on Sunday, as the anchors on state television donned black. “He and Mojtaba Khamenei—son of the 85-year-old Supreme Leader—are the only talked-about candidates for succession. In Iran's conspiratorial political culture, few will believe Raisi’s death was accidental.”